DS Ethereum
Publish: 2021-04-15 04:00:35
1. If this kind of lamp is used, you can ask others to take a look at it for you.
2.
Let me search the Internet for about 8K
3. [MA5600V800R105:5323][global-config]<global-config>-x3d3100
[MA5600V800R105: 5323]
#
[global-config]
<global-config>
terminal user name buildrun_new huawei *[89!GX%`23P+,N">,)UQ1YA!!* 1 2014:08:12:10:43:20 2014:08:12:10:43:20 root 2 8 -----
adsl mode switch-to ADSL
alarm statistics alarmid 0x023000ea
alarm statistics alarmid 0x023000eb
alarm alarmlevel 0x3d310016 major
[MA5600V800R105: 5323]
#
[global-config]
<global-config>
terminal user name buildrun_new huawei *[89!GX%`23P+,N">,)UQ1YA!!* 1 2014:08:12:10:43:20 2014:08:12:10:43:20 root 2 8 -----
adsl mode switch-to ADSL
alarm statistics alarmid 0x023000ea
alarm statistics alarmid 0x023000eb
alarm alarmlevel 0x3d310016 major
4. The transmission system is different. When the SDH time slot is configured, the signal from a to B is straight through, which means that this channel is always on for you whether you use it or not. Unlike Ethernet, Ethernet realizes the communication of the destination site through IP addressing. When the channel is not in use, it does not occupy bandwidth, as long as there is communication service demand, Only in some rules (such as real-time business QoS) to achieve communication, occupy channel bandwidth
the networking configurations of SDH and IP are very different (see the relevant networking information)
the self-healing time and mode of SDH and IP are different
in a word, there is a big difference.
the networking configurations of SDH and IP are very different (see the relevant networking information)
the self-healing time and mode of SDH and IP are different
in a word, there is a big difference.
5.
Ds-2zcn3008 (c) has good effect. The main features of Hikvision 30 times 3 million network integrated camera are as follows:
supports h.265 efficient compression algorithm, greatly reces the bit rate of
3 million pixels progressive scan 1 / 2.8 & quot; CMOS
maximum resolution of 2048x1536
30x optical zoom, focal length of 4.5-135mm
minimum illumination: color 0.5 [email protected]
support ICR infrared filter automatic switching
focus fast and accurate
support digital wide dynamic
support 3d-dnr, low bit rate
complete functions: heartbeat, PTZ control, alarm, audio, user management
application scenario
it is suitable for large warehouse, peripheral monitoring of residential area, wharf, square, school, station, park and other large monitoring places requiring high-definition image quality
ds-2zcn3008 (c) Hikvision 30 times 3 million integrated network camera proct dimension drawing: ds-2zcn3008 (c) Hikvision 30 times 3 million integrated network camera detailed technical parameters:
ds-2zcn3008 (c)
model
model ds-2zcn3008 (c)
name 30 times 3 million 1 / 2.8 & quot; CMOS ICR day and night network HD all in one machine
camera
sensor type 1 / 2.8 & quot; Progressive scan CMOS
signal system PA / NTSC
shutter 1 / 1s ~ 1 / 30, 000 seconds
day night conversion mode ICR infrared filter chip
SNR greater than 52dB
automatic aperture f1.6-f4.4
effective pixel 3 million
video output network coding output
resolution: 50 Hz: 25 FPS (1920x1080) 60 Hz: 30 FPS (1920x1080)
50 Hz: 25 FPS (1280 x720) 60 Hz: 30 FPS (1280 x720)
minimum illumination color: 0.05 UX @ (f1.6, AGC on)
black and white: 0.01ux @ (f1.6, AGC on)
horizontal angle 57.2 – 2.2 degrees (wide-angle telescope)
3D noise rection support
lens
focal length 4.3-129.0mm, 30x optical zoom
aperture f1.6-f4.4
close range 10-1500mm (wide-angle telescope)
zoom speed about 4.1s (optical, Wide angle telescope)
day night conversion mode ICR filter
menu control
exposure mode auto exposure / aperture priority / shutter priority / manual exposure
focus mode auto focus / single focus / manual focus
backlight compensation off / up / down / left / right / center
RS-485 communication protocol / baud rate / address
defect detection support
exposure mode auto exposure / manual focus Exposure / aperture priority / shutter priority
compression standard
video compression standard h.265/h.264
compression output bit rate 32kbps-12mbps
audio compression standard G.722.1, g.711-a aw, g.711-u aw, mp22, G.726, AAC, PCM
Image
maximum image size, maximum resolution up to 1920x1080
image saturation, brightness, The contrast can be adjusted through the client or Internet Explorer
network function
storage function supports micro SD
intelligent alarm, mobile detection, occlusion alarm, memory full, memory error, audio anomaly detection, cross boundary detection, area intrusion detection
supports TCP / IP, HTTP, DHCP, DNS, DDNS, RTP, RTSP, PPPoE, SMTP, NTP, UPnP, SNMP, FTP, 802.1x QoS, HTTPS, IPv6 (SIP, SRTP, optional)
general function, al stream, heartbeat, password protection
function
image quality adjustment, brightness, contrast, sharpness Saturation can be adjusted
White Balance Auto 1 / Auto 2 / indoor / outdoor / manual / incandescent lamp / fluorescent lamp
exposure mode auto exposure / aperture priority / shutter priority / manual exposure
day and night mode auto / color / black and white / timing / alarm input trigger
electronic shutter 1 / 1 second ~ 1 / 30, 000 seconds
wide dynamic off / on
backlight compensation off / on
gain 16 levels adjustable
strong light suppression off / on
bad point compensation support
digital noise rection 3D
other functions sharpness, brightness, saturation, contrast, 3D noise rection
lens initialization built-in
external network port, RS485, arm in / out, ine in / out, CVBS SDHC
external communication RS485 interface, Peco protocol
interface
external interface network port, RS485, arm in / out, ine in / out, CVBS, SDHC
one channel of audio input
one channel of audio output
communication interface, one RJ45 10m / 100M adaptive Ethernet port, one RS-485 interface
one channel of alarm input
one channel of alarm output
interface protocol onvif, psia, CGI ISAPI
General specification
working temperature and humidity - 10 ℃ ~ 60 ℃, humidity less than 90% (no condensation)
power supply DC12V ± 10%, supporting Poe power supply
static power consumption of 2.5W, dynamic power consumption of 4.5w
size (mm) of 74.3 × eighty-one point one × 142mm
weight 320G
6. With ds-5, you can easily develop Linux applications for ARM processor based platforms. It reces the learning difficulty, shortens the development and testing cycle, and helps you quickly build reliable applications. Affordable professional solutions for developers who develop Linux and Android applications and libraries with C / C + +. It uses standard connections such as Ethernet and USB for application debugging and system performance analysis. An end-to-end software development tool for Linux based systems. In addition, it also provides debugging and tracking functions at the bare metal and kernel level, which can be downloaded from 100 million channels
7. See the website below. It's graphic. It's easy to understand.
http://www.huaker.net/index_ Article_ Content.asp?fID_ Article content = 258
switches are divided into ordinary switches and manageable switches.
ordinary switches mainly provide network sharing. They have no management function. They are connected to the network. They are faster than hub.
manageable switches have humanized management functions. There are too many functions. You can study them for several months without any problem It's too late
http://www.huaker.net/index_ Article_ Content.asp?fID_ Article content = 258
switches are divided into ordinary switches and manageable switches.
ordinary switches mainly provide network sharing. They have no management function. They are connected to the network. They are faster than hub.
manageable switches have humanized management functions. There are too many functions. You can study them for several months without any problem It's too late
8. Dir column file name deltree delete directory tree CLS clear screen CD change current directory
file disk disk del delete file format format disk
edit text edit MEM view memory status MD create subdirectory move file Change directory name
more split screen display type display file content Rd delete directory sys make DOS system disk
Ren change file name x directory and file CHKDSK check disk attrib set file attribute
fdisk hard disk partition date display and modification date label set volume label defrag Disk Defrag
MSD system detect path set search directory share file File sharing MemMaker memory optimization management
help restore restore backup file set setting environment variable time display and modify time
tree column directory tree debug random debugger doskey re call DOS command prompt prompt prompt undelete restore deleted file ScanDisk test DOS command is not commonly used to repair disk
diskcomp disk compare append set non executable file path
Expand restore DOS file FastHelp quickly display help information
FC file compare interink start server
setver set version intersvr start client
subst path replace QBASIC integrated environment
vsafe antivirus unformat recover formatted
ver display DOS version number smartdrv set disk accelerator
Vol display disk volume label LH load program into high-end memory
CTTY change control device EMM386 extended memory management
common commands specific introction:
first, dir
display directory file and subdirectory list, ha ha, this of course everyone should know
wildcards (?) can be used? And *),? The table is configured with one character, * the table is configured with any character
*. Suffix
specifies the file to view the suffix. In fact, it can also be "suffix". For example, dir *. Exe equals dir. Exe
/ P
one list screen will be displayed at a time. To view the next screen, press any key on the keyboard
/ W
displays the list in a wide format, with up to five file or directory names on each line
/ s
lists each specified file name that appears in the specified directory and all subdirectories. It is much faster than the search in win environment
dir *. * - & gt; a. Txt write the current directory file list to a.txt
dir *. * / S - & gt; a. Txt write the list of current directory files to a.txt, including files under subdirectories< Second, attrib
displays, sets or deletes the read-only, archive, system and hidden attributes assigned to a file or directory. If used without parameters, attrib displays the properties of all files in the current directory
+ R
set the read-only property
- R
clear the read-only attribute
+ a
set archive file properties
- a
clear archive attributes
+ s
set system properties
- s
clear system attributes
+ H
set hidden attributes
- H
clear hidden attributes< (3) CLS
clear all the information displayed in the command prompt window and return to the empty window, namely "clear screen"
4. Exit
exit the current command interpreter and return to the system< 5. Format
format
/ Q
fast format. Delete the file table and root directory of a previously formatted volume, but do not scan for damaged areas between sectors. Using the / Q command line option, you should format only previously formatted sound volumes< Sixth, ipconfig
displays all the current TCP / IP network configuration values and refreshes the Dynamic Host Configuration Protocol (DHCP) and domain name system (DNS) settings. Use ipconfig without parameters to display the IP address, subnet mask and default gateway of all adapters
/ all
displays the complete TCP / IP configuration information for all adapters
ipconfig is equivalent to winipcfg, which is available on me, 98 and 95. Although Windows XP does not provide a graphical interface like winipcfg command, you can use "network connection" to view and update the IP address. To do this, open a network connection, right-click a network connection, click status, and then click the support tab
this command is most suitable for computers configured to automatically obtain IP addresses. It enables users to determine which TCP / IP configuration values are configured by DHCP, automatic private IP address (APIPA), and other configurations< Seven, MD
create a directory or subdirectory; eight, move
move one or more files from a directory to a specified directory< 9. Nbtstat
displays the NetBIOS statistics, the NetBIOS name table and the NetBIOS name cache of the local computer and the remote computer based on the TCP / IP (NetBt) protocol. Nbtstat can refresh the NetBIOS name cache and registered Windows Internet Name Service (wins) names. Use nbtstat without parameters to display help. Nbtstat command line parameters are case sensitive
- a remotename
displays the NetBIOS name table of the remote computer, where remotename is the NetBIOS computer name of the remote computer
- a IPAddress
displays the NetBIOS name table of the remote computer, whose name is specified by the IP address of the remote computer (separated by decimal point)< 10. Netstat
displays the active TCP connections, ports the computer listens on, Ethernet statistics, IP routing table, IPv4 Statistics (for IP, ICMP, TCP and UDP protocols) and IPv6 Statistics (for IPv6, ICMPv6, TCP over IPv6 and UDP over IPv6 protocols). If it is used without parameters, netstat displays the active TCP connection
- a
displays all active TCP connections and the TCP and UDP ports that the computer is listening on< 11. Ping
verifies the IP level connection with another TCP / IP computer by sending an ICMP echo request message. The reception of the echo response message will be displayed together with the number of round trips. Ping is the main TCP / IP command used to detect network connectivity, reachability and name resolution problems. If there are no parameters, Ping displays help. Name and IP address resolution is its simplest application and also the most used
- T
specifies that Ping can continuously send echo request information to the destination before interruption. To interrupt and display statistics, press ctrl-break. To interrupt and exit Ping, press ctrl-c
- lSize
specifies the length (in bytes) of the "data" field in the sent echo request message. The default value is 32. The maximum size is 65527< 12. Rename (ren)
change the name of the file
for example, Ren *. ABC *. CBA
13 and set
display, set or delete environment variables. If there are no parameters, the set command displays the current environment settings< Shutdown
allows you to shut down or restart a local or remote computer. If no parameter is used, shutdown logs off the current user
- M computername
specifies the computer to shut down
- t XX
set the timer for system shutdown to XX seconds. The default is 20 seconds
- L
log off the current user, which is the default setting- M computername is preferred
- s
shut down the local computer
- R
restart after shutdown
- a
stop closing. Except for - L and computername, other parameters are ignored. During the timeout period, you can only use - A< System file checker (SFC)
win. Scan and verify all protected system files after restarting the computer
/ scan now
scan all protected system files immediately
/ scanning
scan all protected system files at once
/ purgecache
immediately clear the "windows file protection" file cache and scan all protected system files
/ cachesize = x
set the file cache size of windows file protection in MB
16. Type
displays the content of the text file. Use the type command to view the text file or bat file without modifying the file
17, tree
image display path or the directory structure of the disk in the drive
18. X
files and directories, including subdirectories
/ s
non empty directories and subdirectories. If / S is omitted, x will work in a directory
/ E
all subdirectories, including empty ones<
19.
one or more files from one location to another location
20. Del
delete the specified file.
file disk disk del delete file format format disk
edit text edit MEM view memory status MD create subdirectory move file Change directory name
more split screen display type display file content Rd delete directory sys make DOS system disk
Ren change file name x directory and file CHKDSK check disk attrib set file attribute
fdisk hard disk partition date display and modification date label set volume label defrag Disk Defrag
MSD system detect path set search directory share file File sharing MemMaker memory optimization management
help restore restore backup file set setting environment variable time display and modify time
tree column directory tree debug random debugger doskey re call DOS command prompt prompt prompt undelete restore deleted file ScanDisk test DOS command is not commonly used to repair disk
diskcomp disk compare append set non executable file path
Expand restore DOS file FastHelp quickly display help information
FC file compare interink start server
setver set version intersvr start client
subst path replace QBASIC integrated environment
vsafe antivirus unformat recover formatted
ver display DOS version number smartdrv set disk accelerator
Vol display disk volume label LH load program into high-end memory
CTTY change control device EMM386 extended memory management
common commands specific introction:
first, dir
display directory file and subdirectory list, ha ha, this of course everyone should know
wildcards (?) can be used? And *),? The table is configured with one character, * the table is configured with any character
*. Suffix
specifies the file to view the suffix. In fact, it can also be "suffix". For example, dir *. Exe equals dir. Exe
/ P
one list screen will be displayed at a time. To view the next screen, press any key on the keyboard
/ W
displays the list in a wide format, with up to five file or directory names on each line
/ s
lists each specified file name that appears in the specified directory and all subdirectories. It is much faster than the search in win environment
dir *. * - & gt; a. Txt write the current directory file list to a.txt
dir *. * / S - & gt; a. Txt write the list of current directory files to a.txt, including files under subdirectories< Second, attrib
displays, sets or deletes the read-only, archive, system and hidden attributes assigned to a file or directory. If used without parameters, attrib displays the properties of all files in the current directory
+ R
set the read-only property
- R
clear the read-only attribute
+ a
set archive file properties
- a
clear archive attributes
+ s
set system properties
- s
clear system attributes
+ H
set hidden attributes
- H
clear hidden attributes< (3) CLS
clear all the information displayed in the command prompt window and return to the empty window, namely "clear screen"
4. Exit
exit the current command interpreter and return to the system< 5. Format
format
/ Q
fast format. Delete the file table and root directory of a previously formatted volume, but do not scan for damaged areas between sectors. Using the / Q command line option, you should format only previously formatted sound volumes< Sixth, ipconfig
displays all the current TCP / IP network configuration values and refreshes the Dynamic Host Configuration Protocol (DHCP) and domain name system (DNS) settings. Use ipconfig without parameters to display the IP address, subnet mask and default gateway of all adapters
/ all
displays the complete TCP / IP configuration information for all adapters
ipconfig is equivalent to winipcfg, which is available on me, 98 and 95. Although Windows XP does not provide a graphical interface like winipcfg command, you can use "network connection" to view and update the IP address. To do this, open a network connection, right-click a network connection, click status, and then click the support tab
this command is most suitable for computers configured to automatically obtain IP addresses. It enables users to determine which TCP / IP configuration values are configured by DHCP, automatic private IP address (APIPA), and other configurations< Seven, MD
create a directory or subdirectory; eight, move
move one or more files from a directory to a specified directory< 9. Nbtstat
displays the NetBIOS statistics, the NetBIOS name table and the NetBIOS name cache of the local computer and the remote computer based on the TCP / IP (NetBt) protocol. Nbtstat can refresh the NetBIOS name cache and registered Windows Internet Name Service (wins) names. Use nbtstat without parameters to display help. Nbtstat command line parameters are case sensitive
- a remotename
displays the NetBIOS name table of the remote computer, where remotename is the NetBIOS computer name of the remote computer
- a IPAddress
displays the NetBIOS name table of the remote computer, whose name is specified by the IP address of the remote computer (separated by decimal point)< 10. Netstat
displays the active TCP connections, ports the computer listens on, Ethernet statistics, IP routing table, IPv4 Statistics (for IP, ICMP, TCP and UDP protocols) and IPv6 Statistics (for IPv6, ICMPv6, TCP over IPv6 and UDP over IPv6 protocols). If it is used without parameters, netstat displays the active TCP connection
- a
displays all active TCP connections and the TCP and UDP ports that the computer is listening on< 11. Ping
verifies the IP level connection with another TCP / IP computer by sending an ICMP echo request message. The reception of the echo response message will be displayed together with the number of round trips. Ping is the main TCP / IP command used to detect network connectivity, reachability and name resolution problems. If there are no parameters, Ping displays help. Name and IP address resolution is its simplest application and also the most used
- T
specifies that Ping can continuously send echo request information to the destination before interruption. To interrupt and display statistics, press ctrl-break. To interrupt and exit Ping, press ctrl-c
- lSize
specifies the length (in bytes) of the "data" field in the sent echo request message. The default value is 32. The maximum size is 65527< 12. Rename (ren)
change the name of the file
for example, Ren *. ABC *. CBA
13 and set
display, set or delete environment variables. If there are no parameters, the set command displays the current environment settings< Shutdown
allows you to shut down or restart a local or remote computer. If no parameter is used, shutdown logs off the current user
- M computername
specifies the computer to shut down
- t XX
set the timer for system shutdown to XX seconds. The default is 20 seconds
- L
log off the current user, which is the default setting- M computername is preferred
- s
shut down the local computer
- R
restart after shutdown
- a
stop closing. Except for - L and computername, other parameters are ignored. During the timeout period, you can only use - A< System file checker (SFC)
win. Scan and verify all protected system files after restarting the computer
/ scan now
scan all protected system files immediately
/ scanning
scan all protected system files at once
/ purgecache
immediately clear the "windows file protection" file cache and scan all protected system files
/ cachesize = x
set the file cache size of windows file protection in MB
16. Type
displays the content of the text file. Use the type command to view the text file or bat file without modifying the file
17, tree
image display path or the directory structure of the disk in the drive
18. X
files and directories, including subdirectories
/ s
non empty directories and subdirectories. If / S is omitted, x will work in a directory
/ E
all subdirectories, including empty ones<
19.
one or more files from one location to another location
20. Del
delete the specified file.
9. SDH special line is in Wan ~ its transmission efficiency is absolutely higher than that of SDH Ethernet ~ and SDH Ethernet is just an applied term of SDH, which is far from the real SDH. One is national / provincial Wan, and the other is personal small business data special line. You can learn about SDH.
SDH
[first, the concept of SDH
SDH (synchronous digital hierarchy, Synchronous digital architecture (SDIs) is a kind of integrated information transmission network which integrates multiplexing, line transmission and switching functions and is operated by a unified network management system. It is a synchronous optical network (SONET) proposed by Bell Institute of communication technology. In 1988, CCITT (now ITU-T) accepted the concept of SONET and renamed it SDH, making it a general technical system not only suitable for optical fiber, but also for microwave and satellite transmission. It can realize many functions such as effective network management, real-time business monitoring, dynamic network maintenance, intercommunication between different manufacturers' equipment, greatly improve the utilization rate of network resources, rece the cost of management and maintenance, and realize flexible, reliable and efficient network operation and maintenance. Therefore, it is a hot spot in the development and application of transmission technology in the field of information in the world, It is widely valued by people< Second, the birth of SDH technology has its inevitability. With the development of communication, the information required to be transmitted is not only voice, but also text, data, image and video. In addition to the development of digital communication and computer technology, in the 1970s and 1980s, T1 (DS1) / E1 carrier system (1.544 / 2.048mbps), X.25 frame relay, ISDN (Integrated Services Digital Network) and FDDI (optical fiber distributed data interface) and other network technologies appeared one after another. With the advent of the information society, people hope that the modern information transmission network can provide various circuits and services quickly, economically and effectively. However, e to the monotony of services, the complexity of expansion and the limitation of bandwidth, it is useless to modify or improve the above network technologies only within the original framework. SDH is developed in this context. In all kinds of broadband optical access network technology, the access network system using SDH technology is the most common. The birth of SDH solves the problem that the bandwidth limitation of access media can't keep up with the development of backbone network and user service requirements, and proces the access between user and core network; Bottleneck & quot; At the same time, it improves the utilization of a large amount of bandwidth in the transmission network. Since the introction of SDH technology in the 1990s, it has been a mature and standard technology. It is widely used in the backbone network, and the price is getting lower and lower. The application of SDH technology in the access network can bring the huge bandwidth advantages and technical advantages of SDH technology in the core network into the access network field, and make full use of SDH synchronous multiplexing, standardized optical interface, strong network management ability, high efficiency and high efficiency Flexible network topology capability and high reliability bring benefits, and benefit from the construction and development of access network in the long term< Third, the basic transmission principle of SDH. The information structure level of SDH is called synchronous transport mole STM-N (n = 1,4,16,64). The most basic mole is STM-1. Four STM-1 are synchronously multiplexed to form STM-4, and 16 STM-1 or four STM-4 are synchronously multiplexed to form STM-16; SDH uses block frame structure to carry information, and each frame consists of 9 vertical lines and 270 horizontal lines × The whole frame structure is divided into three areas: section overhead (SDH) area, STM-N payload area and management unit pointer (AU PTR) area. The section overhead area is mainly used for network operation, management, maintenance and assignment to ensure the normal and flexible transmission of information, It is divided into regenerator section overhead (RSOH) and multiplex section overhead (msoh); The payload area is used to store the real bits for information services and a small amount of channel overhead bytes for channel maintenance and management; The management unit pointer is used to indicate the exact position of the first byte of information in the payload area in the STM-N frame, so that the payload can be separated correctly when receiving. The frame of SDH is transmitted in sequence from left to right and from top to bottom. The transmission time of each frame is 125 μ s. Transmit 1 / 125 per second × For STM-1, the byte per frame is 8 bits × nine × two hundred and seventy × 1) = 19440 bit, then the transmission rate of STM-1 is 19440 bit × 8000=155.520Mbit／s The transmission rate of STM-4 is 4 × 155.520Mbit／s=622.080Mbit／s The transmission rate of STM-16 is 16 × 520 (or 4 × 622.080=2488.320Mbit／s
when SDH transmits service signals, all kinds of service signals need to go through three steps: mapping, positioning and multiplexing. Mapping is the process of loading signals of various rates into corresponding standard container (c) through code speed adjustment, and then adding channel overhead (POH) to form virtual container (VC). Frame phase deviation is called frame offset; Positioning is the process of receiving frame offset information into Tu or Au, which is realized by the function of Tu PTR or AU PTR; Multiplexing is the process of adjusting the code speed of multiple low price channel layer signals into the high price channel or multiple high price channel layer signals into the multiplexing layer< The characteristics of SDH are as follows: (1) SDH transmission system has a unified frame structure in the world, standard digital transmission rate and standard optical interface, which makes the network management system interworking, so it has good horizontal compatibility, It can be fully compatible with the existing PDH and accommodate all kinds of new service signals, forming a global unified digital transmission system standard and improving the reliability of the network
(2) the arrangement of different levels of code streams in the frame structure payload area of SDH access system is very regular, and the payload is synchronized with the network. It can directly insert the high-speed signal into the low-speed branch signal at one time by using software, which realizes the characteristics of one-time multiplexing, and overcomes the process of PDH quasi synchronous multiplexing to decompose all the high-speed signals step by step and then regenerate them, Because DXC is greatly simplified, the back-to-back interface multiplexing equipment is reced, and the service transmission transparency of the network is improved
(3) because of the use of advanced add drop multiplexer (ADM), digital cross connect (DXC), network self-healing function and reorganization function, it is very powerful and has a strong survival rate. Because 5% of the signal overhead bits are arranged in the SDH frame structure, its network management function is particularly powerful, and can form a unified network management system, which plays a positive role in network automation, intelligence, channel utilization, and recing network maintenance cost and survivability
(4) because SDH has many kinds of network topologies, its network is very flexible. It can enhance the functions of network monitoring, operation management and automatic configuration, optimize the network performance, and make the network flexible, safe and reliable, so that the network functions are very complete and diversified
(5) SDH has the performance of transmission and switching. The composition of its series of devices can realize the network of different levels and topologies through the free combination of function blocks, which is very flexible
(6) SDH is not a special transmission medium, it can be used in twisted pair and coaxial cable, but it needs optical fiber to transmit high data rate. This characteristic shows that SDH is suitable for both trunk and branch channels. For example, SDH is used in national and provincial CATV trunk network in China, and it is also compatible with HFC
(7) from the perspective of OSI model, SDH belongs to the lowest physical layer, and there is no strict restriction on its upper layer, so it is convenient to use various network technologies on SDH to support ATM or IP transmission
(8) SDH is strictly synchronized, which ensures the stability and reliability of the whole network, reces bit error, and is easy to reuse and adjust
(9) the standard open optical interface can achieve horizontal compatibility on the basic optical cable segment, recing the networking cost< 5. The application of SDH
e to the above-mentioned characteristics of SDH, it has made great progress in the field of Wan and private network. Telecom operators such as China Telecom, China Unicom, radio and television have built large-scale backbone optical transmission network based on SDH. Large capacity SDH loop is used to carry IP service, ATM service or directly rent circuit to enterprises and institutions. And some large private networks also use SDH technology, set up the SDH optical loop inside the system to carry all kinds of services. For example, the power system uses SDH loop to carry internal data, remote control, video, voice and other services
for those units which are more urgent in networking and have no possibility to set up a dedicated SDH loop, many of them use the way of renting telecom operators' circuits. Due to the characteristics of SDH based on physical layer, the unit can carry all kinds of services on the leased circuit without the limitation of transmission. There are many ways to carry, which can be the use of TDM technology-based integrated multiplexing equipment to achieve multi service multiplexing, or IP based equipment to achieve multi service packet switching. SDH technology can guarantee the bandwidth of leased circuit, and its security is better than VPN. SDH leased line has been widely used in government agencies and enterprises that attach great importance to security. Generally speaking, SDH can provide E1, E3, STM-1 or STM-4 interfaces, which can fully meet various bandwidth requirements. At the same time, in terms of price, it has been accepted by most units< As a new generation of ideal transmission system, SDH has the advantages of automatic route selection, convenient upper and lower circuits, strong maintenance, control and management functions, unified standards, and convenient transmission of higher rate services, which can well meet the needs of the rapid development of communication network. So far, SDH has been applied and developed unprecedentedly. In the aspect of standardization, a series of suggestions that have been established and will be established have basically covered all aspects of SDH. It is widely used in trunk network, long distance network, relay network and access network. And in optical fiber communication, microwave communication, satellite communication also actively carry out research and application
in recent years, VOD TV, multimedia services and other broadband services have sprung up, providing a broad space for SDH applications in the access network. The advantages of applying SDH technology to access network are as follows: 1) SDH can provide ideal network performance and service reliability for large enterprise users who require high reliability and high quality services. 2) It can extend the scope of network management to the client and simplify the maintenance. 3) With the inherent flexibility of SDH, network operators can provide users with long-term and short-term business requirements faster and more effectively
it can be predicted that SDH technology will continue to develop. With the development of network, it will further provide broadband services for end users, and will be more widely used in meeting the opportunities and challenges brought by ATM, CATV, multimedia, Internet and all-optical network< To sum up, SDH has become the mainstream of transmission network development with its obvious advantages. SDH technology is combined with some advanced technologies, such as optical wavelength division multiplexing (WDM), ATM technology
SDH
[first, the concept of SDH
SDH (synchronous digital hierarchy, Synchronous digital architecture (SDIs) is a kind of integrated information transmission network which integrates multiplexing, line transmission and switching functions and is operated by a unified network management system. It is a synchronous optical network (SONET) proposed by Bell Institute of communication technology. In 1988, CCITT (now ITU-T) accepted the concept of SONET and renamed it SDH, making it a general technical system not only suitable for optical fiber, but also for microwave and satellite transmission. It can realize many functions such as effective network management, real-time business monitoring, dynamic network maintenance, intercommunication between different manufacturers' equipment, greatly improve the utilization rate of network resources, rece the cost of management and maintenance, and realize flexible, reliable and efficient network operation and maintenance. Therefore, it is a hot spot in the development and application of transmission technology in the field of information in the world, It is widely valued by people< Second, the birth of SDH technology has its inevitability. With the development of communication, the information required to be transmitted is not only voice, but also text, data, image and video. In addition to the development of digital communication and computer technology, in the 1970s and 1980s, T1 (DS1) / E1 carrier system (1.544 / 2.048mbps), X.25 frame relay, ISDN (Integrated Services Digital Network) and FDDI (optical fiber distributed data interface) and other network technologies appeared one after another. With the advent of the information society, people hope that the modern information transmission network can provide various circuits and services quickly, economically and effectively. However, e to the monotony of services, the complexity of expansion and the limitation of bandwidth, it is useless to modify or improve the above network technologies only within the original framework. SDH is developed in this context. In all kinds of broadband optical access network technology, the access network system using SDH technology is the most common. The birth of SDH solves the problem that the bandwidth limitation of access media can't keep up with the development of backbone network and user service requirements, and proces the access between user and core network; Bottleneck & quot; At the same time, it improves the utilization of a large amount of bandwidth in the transmission network. Since the introction of SDH technology in the 1990s, it has been a mature and standard technology. It is widely used in the backbone network, and the price is getting lower and lower. The application of SDH technology in the access network can bring the huge bandwidth advantages and technical advantages of SDH technology in the core network into the access network field, and make full use of SDH synchronous multiplexing, standardized optical interface, strong network management ability, high efficiency and high efficiency Flexible network topology capability and high reliability bring benefits, and benefit from the construction and development of access network in the long term< Third, the basic transmission principle of SDH. The information structure level of SDH is called synchronous transport mole STM-N (n = 1,4,16,64). The most basic mole is STM-1. Four STM-1 are synchronously multiplexed to form STM-4, and 16 STM-1 or four STM-4 are synchronously multiplexed to form STM-16; SDH uses block frame structure to carry information, and each frame consists of 9 vertical lines and 270 horizontal lines × The whole frame structure is divided into three areas: section overhead (SDH) area, STM-N payload area and management unit pointer (AU PTR) area. The section overhead area is mainly used for network operation, management, maintenance and assignment to ensure the normal and flexible transmission of information, It is divided into regenerator section overhead (RSOH) and multiplex section overhead (msoh); The payload area is used to store the real bits for information services and a small amount of channel overhead bytes for channel maintenance and management; The management unit pointer is used to indicate the exact position of the first byte of information in the payload area in the STM-N frame, so that the payload can be separated correctly when receiving. The frame of SDH is transmitted in sequence from left to right and from top to bottom. The transmission time of each frame is 125 μ s. Transmit 1 / 125 per second × For STM-1, the byte per frame is 8 bits × nine × two hundred and seventy × 1) = 19440 bit, then the transmission rate of STM-1 is 19440 bit × 8000=155.520Mbit／s The transmission rate of STM-4 is 4 × 155.520Mbit／s=622.080Mbit／s The transmission rate of STM-16 is 16 × 520 (or 4 × 622.080=2488.320Mbit／s
when SDH transmits service signals, all kinds of service signals need to go through three steps: mapping, positioning and multiplexing. Mapping is the process of loading signals of various rates into corresponding standard container (c) through code speed adjustment, and then adding channel overhead (POH) to form virtual container (VC). Frame phase deviation is called frame offset; Positioning is the process of receiving frame offset information into Tu or Au, which is realized by the function of Tu PTR or AU PTR; Multiplexing is the process of adjusting the code speed of multiple low price channel layer signals into the high price channel or multiple high price channel layer signals into the multiplexing layer< The characteristics of SDH are as follows: (1) SDH transmission system has a unified frame structure in the world, standard digital transmission rate and standard optical interface, which makes the network management system interworking, so it has good horizontal compatibility, It can be fully compatible with the existing PDH and accommodate all kinds of new service signals, forming a global unified digital transmission system standard and improving the reliability of the network
(2) the arrangement of different levels of code streams in the frame structure payload area of SDH access system is very regular, and the payload is synchronized with the network. It can directly insert the high-speed signal into the low-speed branch signal at one time by using software, which realizes the characteristics of one-time multiplexing, and overcomes the process of PDH quasi synchronous multiplexing to decompose all the high-speed signals step by step and then regenerate them, Because DXC is greatly simplified, the back-to-back interface multiplexing equipment is reced, and the service transmission transparency of the network is improved
(3) because of the use of advanced add drop multiplexer (ADM), digital cross connect (DXC), network self-healing function and reorganization function, it is very powerful and has a strong survival rate. Because 5% of the signal overhead bits are arranged in the SDH frame structure, its network management function is particularly powerful, and can form a unified network management system, which plays a positive role in network automation, intelligence, channel utilization, and recing network maintenance cost and survivability
(4) because SDH has many kinds of network topologies, its network is very flexible. It can enhance the functions of network monitoring, operation management and automatic configuration, optimize the network performance, and make the network flexible, safe and reliable, so that the network functions are very complete and diversified
(5) SDH has the performance of transmission and switching. The composition of its series of devices can realize the network of different levels and topologies through the free combination of function blocks, which is very flexible
(6) SDH is not a special transmission medium, it can be used in twisted pair and coaxial cable, but it needs optical fiber to transmit high data rate. This characteristic shows that SDH is suitable for both trunk and branch channels. For example, SDH is used in national and provincial CATV trunk network in China, and it is also compatible with HFC
(7) from the perspective of OSI model, SDH belongs to the lowest physical layer, and there is no strict restriction on its upper layer, so it is convenient to use various network technologies on SDH to support ATM or IP transmission
(8) SDH is strictly synchronized, which ensures the stability and reliability of the whole network, reces bit error, and is easy to reuse and adjust
(9) the standard open optical interface can achieve horizontal compatibility on the basic optical cable segment, recing the networking cost< 5. The application of SDH
e to the above-mentioned characteristics of SDH, it has made great progress in the field of Wan and private network. Telecom operators such as China Telecom, China Unicom, radio and television have built large-scale backbone optical transmission network based on SDH. Large capacity SDH loop is used to carry IP service, ATM service or directly rent circuit to enterprises and institutions. And some large private networks also use SDH technology, set up the SDH optical loop inside the system to carry all kinds of services. For example, the power system uses SDH loop to carry internal data, remote control, video, voice and other services
for those units which are more urgent in networking and have no possibility to set up a dedicated SDH loop, many of them use the way of renting telecom operators' circuits. Due to the characteristics of SDH based on physical layer, the unit can carry all kinds of services on the leased circuit without the limitation of transmission. There are many ways to carry, which can be the use of TDM technology-based integrated multiplexing equipment to achieve multi service multiplexing, or IP based equipment to achieve multi service packet switching. SDH technology can guarantee the bandwidth of leased circuit, and its security is better than VPN. SDH leased line has been widely used in government agencies and enterprises that attach great importance to security. Generally speaking, SDH can provide E1, E3, STM-1 or STM-4 interfaces, which can fully meet various bandwidth requirements. At the same time, in terms of price, it has been accepted by most units< As a new generation of ideal transmission system, SDH has the advantages of automatic route selection, convenient upper and lower circuits, strong maintenance, control and management functions, unified standards, and convenient transmission of higher rate services, which can well meet the needs of the rapid development of communication network. So far, SDH has been applied and developed unprecedentedly. In the aspect of standardization, a series of suggestions that have been established and will be established have basically covered all aspects of SDH. It is widely used in trunk network, long distance network, relay network and access network. And in optical fiber communication, microwave communication, satellite communication also actively carry out research and application
in recent years, VOD TV, multimedia services and other broadband services have sprung up, providing a broad space for SDH applications in the access network. The advantages of applying SDH technology to access network are as follows: 1) SDH can provide ideal network performance and service reliability for large enterprise users who require high reliability and high quality services. 2) It can extend the scope of network management to the client and simplify the maintenance. 3) With the inherent flexibility of SDH, network operators can provide users with long-term and short-term business requirements faster and more effectively
it can be predicted that SDH technology will continue to develop. With the development of network, it will further provide broadband services for end users, and will be more widely used in meeting the opportunities and challenges brought by ATM, CATV, multimedia, Internet and all-optical network< To sum up, SDH has become the mainstream of transmission network development with its obvious advantages. SDH technology is combined with some advanced technologies, such as optical wavelength division multiplexing (WDM), ATM technology
10. The specific model you mentioned is not found, but DS should start with a gun or ball type machine of Hikvision's family, which requires a hard disk video recorder to work together. Without a video recorder, you can't view video and video playback, let alone remote viewing. That is to say, all interactive functions are provided by the video recorder, If you only want a simple camera to record video and view playback, you can buy Hikvision's Fluorite series, which also has many models. You can choose C6 for simple video and PTZ, which is convenient, simple and big brand. All of them are Hikvision's procts.
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