telecom nouns

SS7 (七号信令)

         Signaling System No. 7 (SS7) is a set (是一套而不是单一的协议) of telephony signaling protocols developed in 1975, which is used to set up and tear down most of the world’s public switched telephone network (PSTN) telephone calls. It also performs number translation, local number portability, prepaid billing, Short Message Service (SMS), and other mass market services.

SS7 point code ( SPC )

      An SS7 point code is similar to an IP address in an IP network. It is a unique address for a node (Signaling Point, or SP), used in MTP layer 3 to identify the destination of a message signal unit (MSU).


Signal Transfer Point ( STP )

      A Signal Transfer Point (STP) is a router that relays SS7 messages between signaling end-points (SEPs) and other signaling transfer points (STPs). Typical SEPs include service switching points (SSPs) and service control points (SCPs). The STP is connected to adjacent SEPs and STPs via signaling links. Based on the address fields of the SS7 messages, the STP routes the messages to the appropriate outgoing signaling link. Edge STPs can also route based upon message body content using deep packet inspection techniques, and can provide address translations and screen content to limit the transfer of messages with dubious content or sent from unreliable sources. To meet stringent reliability requirements, STPs are typically provisioned in mated pairs.




      Transaction Capabilities Application Part, is a protocol for Signalling System 7 networks. Its primary purpose is to facilitate multiple concurrent dialogs between the same sub-systems on the same machines, using Transaction IDs to differentiate these, similar to the way TCP ports facilitate multiplexing connections between the same IP addresses on the Internet.
TCAP uses ASN.1 BER encoding, as well as the protocols it encapsulates, namely MAP in mobile phone networks or INAP in Intelligent Networks.

CAMEL Application Part ( CAP )

      The CAMEL Application Part (CAP) is a signalling protocol used in the Intelligent Network (IN) architecture
是 智能网( IN ) 的信令协议, 与智能网通信都需要使用 CAP


      是 SS7 的 user layer adaptation , 使用 IP 通信 ,用 SCTP 协议
也可以理解为 M3UA via SCTP protocol


SSN number
      ss7 sub system number


      A PBX (private branch exchange) is a telephone system within an enterprise that switches calls between enterprise users on local lines while allowing all users to share a certain number of external phone lines. The main purpose of a PBX is to save the cost of requiring a line for each user to the telephone company’s central office.   (类似家用路由器)

Global Title vs. Point Code

      A Global Title (GT) is an address used in the SCCP protocol for routing signaling messages on telecommunications networks. In theory, a global title is a unique address which refers to only one destination, though in practice destinations can change over time.
The Global Title is similar in purpose on the PSTN to the host name on the internet. In design, however, global titles are quite different. The structure is usually hierarchical, the value can be of variable length, and is not necessarily a wholly numeric value—though it often is for issues of backwards compatibility and association with regular telephone numbers.
An SS7 point code is similar to an IP address in an IP network. It is a unique address for a node (Signaling Point, or SP), used in MTP layer 3 to identify the destination of a message signal unit (MSU).
In such a message you will find an OPC (Originating Point Code) and a DPC (Destination Point Code); sometimes documents also refer to it as a signaling point code. Depending on the network, a point code can be 24 bits (North America, China), 16 bits (Japan), or 14 bits (ITU standard, International SS7 network and most countries) in length.
For example Global titles belong to your mobile network looks like your mobile number: +xx248283828 where xx is your contry code
Pont code looks like: 8578, 600 etc.


      MTP2 is the Data Link layer used with in SS7; it is used to carry MTP3 traffic from point to point.

centos commands

                              common command 

  • find certain folder :     find / -type d -name ‘folderName’
  • find file :   去掉 -type d 
  • copy all files in current folder to another path  :

cp -r /home/server/folder/test/*      /home/server/

if want to copy all files and all subfolders ,  use

cp -R * /home/tom/backup

  • rm *  will delete all files in a folder ,  if files include write-protected ,  use rm -f * 
    • make .sh file executable :        chmod +x filename
    • rename folder or file :        mv hkg.csl-collector1    my.maxis.collector1
    • list all file include some string :      ls somestring*
    • delete folder and all files include subfolder :     sudo rm -r foldername
    • check if centos is 32 or 64 bits : uname -a
    • check file status : stat filename
    • monitor runtime log :  tail -f bridge.log 
    • monitor last 10 lines of log file : tail -n10 bridge.log
    • check folder size :    du -sh /var/Asterisk/asterisk  , this is check one folder size , If want to check every folder size under certain path :   du -sh *
      • check if selinux is opened :  sestatus
      • search certain text in some folder
        grep -r “language_attributes” /var/www/html/wordpress/*

  •       search certain text in all the folders and their sub fold :
  •             grep  wordToSearch  * -R 
    • copy all files in one folder to another folder :

  cp -r /var/modules/tinyRadiusServer/*      /var/modules/tinyRadiusClient

  • 把某目录加入到系统路径



  • show folder structure as tree


  • list top 10 size fold of a special folder :

  • compress and decompress

uncompress   tar xvzf XXXX.tar.gz 


tar -xjf test.tbz


For compress :


  • -z : Compress archive using gzip program
  • -c : Create archive
  • -v : Verbose i.e display progress while creating archive
  • -f : Archive File name
  • chown

  • Firewall

centos7 open http 8080 port :



  • add user


  • 权限

drwxrwxr-x     :  chmod 775

-rw-rw-r–         :  chmod    664

数字和字母的转换关系 :


  • 看centos 版本

  • 32还是 64位

  • 把某文件夹所有文件打包成zip



                            nano command 

  • select all

To select text in nano, move the cursor to the start of the text you want to select, press the Alt-A key combination to mark the start, then move the cursor to the end of the section you want to select. press Ctrl+K to cut your selection and Ctrl+U to paste it.

  • 复制粘贴

ctrl +6 设置起始点

选中要copy的部分之后, alt+6

然后到要粘贴的位置  ctrl + u


修改 /etc/supervisord.conf 以后, 需要执行







work together with ctags 

use asterisk project as example :

goto folder :  /usr/src/asterisk-certified-13.18-cert3

run  : ctags -R  will  generate a  file named: tags

then for example  :

cd main

vim asterisk.c

set tags=/usr/src/asterisk-certified-13.18-cert3/tags

after doing that ,  vim already know where to find tags




可以在 vimrc 添加以下命令


then when stay cursor in some constant or function name and press :

CTRL +  ]

vim will  guide u  into where this tag define

CTRL + t  will go back to previous file

quit split window :

more ctags skills

vim 复制 剪切 删除 copy

  • VIM serach 

To find a word in Vi/Vim, simply type the / or ? key, followed by the word you’researching for. Once found, you can press the n key to go directly to the next occurrence of the word.



show file name  :

quit without saving

  • vim中使用cscope

cscope比ctags 好,更容易找到 函数定义之类


Centos 7  command 

  • 看 service 状态