STUN和TURN技术浅析

STUN和TURN技术浅析

STUN, STUNT, XSTUNT 介绍

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STUN

STUN (Session Traversal Utilities for NAT) is a standardized set of methods and a network protocol to allow an end host to discover its public IP address if it is located behind a NAT. It is used to permit NAT traversal for applications of real-time voice, video, messaging, and other interactive IP communications. It is documented in RFC 5389. The STUN URI scheme is documented in RFC 7064. STUN is intended to be a tool to be used by other protocols, such as ICE.

The STUN protocol allows applications operating behind a network address translator (NAT) to discover the presence of the network address translator and to obtain the mapped (public) IP address (NAT address) and port number that the NAT has allocated for the application's User Datagram Protocol (UDP) connections to remote hosts. The protocol requires assistance from a third-party network server (STUN server) located on the opposing (public) side of the NAT, usually the public Internet.

其他资料:

1. Characterization and Measurement of TCP Traversal through NATs and FirewallsPDF:

2. Peer-to-Peer Communication Across Network Address Translators:google搜素"穿越NAT的p2p通信方法研究

restund 安装使用手册
http://nil.uniza.sk/sip/installing-and-configuring-restund-stunturn-server

Installing and configuring Restund - STUN/TURN server
Submitted by paulus on Tue, 02/21/2012 - 23:02

This guide describes how to install and configure RESTUND STUN/TURN server for supporting TURN functionality. 

This sollution is still in TESTING STATE!!!

TURN server seems to work properly, but sometimes the klient channel allocation on server side is not working and the media stream wont start!

Testing with: Restund v0.4.0, Kamailio v3.2, X-lite 4.

 

 

First we need to install compiler g++ and make:

 $apt-get install g++ make

 

The instalation and configuration of RESTUND STUN/TURN server takes more steps (official site http://www.creytiv.com/restund.html). 

The first sten is installing libre (Toolkit library for asynchronous network IO with protocol stacks including SIP, SDP, RTP, STUN, TURN, ICE, BFCP and DNS):

 $wget http://www.creytiv.com/pub/re-0.4.0.tar.gz

 $tar xf re-0.4.0.tar.gz

 $cd re-0.4.0/

 $make

 $make install

Now we can install the STUN/TURN server:

 $wget http://www.creytiv.com/pub/restund-0.4.0.tar.gz

 $tar xf restund-0.4.0.tar.gz

 $cd restund-0.4.0/

 $make

 $make install

And finally the configuration file. The sample configuration file is in restund etc directory:

joe .../restund-0.4.0/etc/restund.conf

Hint: Some notes about configuration file items could be find in .../restund/docs/restund.txt

 

Following changes in configuration file will provide the basic TURN server functionality:

debug                     yes
syncinterval              600
udp_listen                158.193.139.47:3478 #YOUR IP ADDRESS
udp_listen                158.193.139.48:3478 #YOUR IP ADDRESS
udp_sockbuf_size          524288
tcp_listen                158.193.139.47:3478 #YOUR IP ADDRESS
tcp_listen                158.193.139.48:3478 #YOUR IP ADDRESS

# modules
module_path               /usr/local/lib/restund/modules
module                    stat.so
module                    binding.so
#module                   auth.so   #no authentication configured, so comment
module                    turn.so
#module                   mysql_ser.so  #Mysql  not yes supported, so comment
module                    syslog.so
module                    status.so

# turn
turn_max_allocations   512
turn_max_lifetime      600
turn_relay_addr        158.193.139.47 #YOUR IP ADDRESS
#turn_relay_addr6      ::1 #comment if not using IPv6 

#Mysql  not yes supported, so comment following lines
# mysql
#mysql_host                     localhost
#mysql_user                     ser
#mysql_pass                     heslo
#mysql_db                        ser

 

 After making changes above copy the configuration file into /etc/ directory:

 $cp .../restund-0.4.0/etc/restund.conf /etc/

 

刚安装完 *.so动态库，需要刷新动态库的信息 ldconfig -p 可以看到动态库信息是否更新了，不更新，无法使用
 $sudo ldconfig


To run RESTUND STUN/TURN server use following command:

 $restund /etc/restund.conf

With debbuging mode on following message (or similar) appear:



udp listen: 158.193.139.47:3478  udp listen: 158.193.139.48:3478
tcp listen: 158.193.139.47:3478
tcp listen: 158.193.139.48:3478
stat: module loaded
binding: module loaded
turn: lifetime=120 ext=158.193.139.47 ext6=? bsz=1024
syslog: module loaded facility=24
status: module loaded (udp=127.0.0.1:33000 http=158.193.139.47:8080)

 

To see the actual status of your TURN server, we need to install apache server:

 $apt-get install apache2

 

And next do following changes in configuration file:

# status
#status_udp_addr      127.0.0.1 #comment
#status_udp_port      33000     #comment
status_http_addr      158.193.139.47 #YOUR IP ADDRESS
status_http_port      8080 #port for http access

 

Restart your RESTUND STUN/TURN server. Now you are able to if your server is running and how long with your web browser:

http://YOUR_IP_ADDRESS:8080