Librenix
Headlines | Linux | Apps | Coding | BSD | Admin | News
Information for Linux System Administration 

Configuring IGMP in a LAN for Multicast IPTV Streams

Up
vote
Down

The basic mechanism of delivery of TV channels to subscribers in local area networks is IP multicast. The peculiarity of this technology is that all multimedia streams are always broadcasted into the network regardless of the number of active subscribers at the moment. For instance, to stream 20 TV channels at the average bitrate 4 Mbps per channel it is required around 4*20=80 Mbps of total bandwidth. These 80 Mbps are streamed into the network even if no one of the subscribers is connected at the moment or, e.g., if the number of active subscribers is lot more than 1000.

Multicasting of multimedia content into a LAN is concerned with the necessity to strictly control which packets should be delivered and to which recipient. It is required to avoid the case when all packets are delivered to all subscribers. In this case the client devices are spending their resources on processing unbidden packets and, as a result, are not able to cope. The subscriber should receive only packets of the stream he has requested. For that the subscriber's equipment makes a query via IGMP to enter a certain multicast group. After that this request is registered on the router; in terms of IGMP this device is called "Querier". After successful registration, the Ethernet switch begins copying multicast packets destined for this group to the port the subscriber is connected to. Due to IGMP, Ethernet switches can determine which multicast packets should be copied to the subscriber's port and which should not.

In the present article configuring of IGMP in a LAN with Ethernet switch Cisco Catalyst 2950T and a Linux-based DVB to IP gateway, produced by NetUP, is discussed. The clients' devices used are Amino AmiNET110 IP set-top box and a PC with Windows or Linux OS and multimedia player VLC.
 read more | mail this link | score:8452 | -John_M.Stagger, July 10, 2007 (Updated: August 29, 2008)
More Sysadmin articles...

Buy Abstract Art Prints

admin headlines

Tutorial: Replace Windows with OpenSUSE 12.3 Linux

Tutorial: Automated File Replication on 2 Storage Servers with GlusterFS on CentOS 6.3

KVM on CentOS 6.3

Run Headless VirtualBox 4.1 on Fedora 17 Server

Run Linux Mint Debian Cinnamon in VirtualBox

Tutorial: Install KVM, libvirt, Bridged Networking on CentOS 6.2

Tutorial: Install Lighttpd, PHP5 and MySQL on Ubuntu 11.10

File System Encryption on CentOS 6

Two-Factor Authentication on Ubuntu with CAS and WiKID

 

Firefox sidebar

Site map

Site info

News feed

Features

Login
(to post)

Search

 
Articles are owned by their authors.   © 2000-2012 Ray Yeargin