A multiplexing scheme for H.323 voice-over-IP applications

Abstract

Abstract-Voice communications such as telephony are delay sensitive. Existing voice-over-IP (VoIP) applications transmit voice data in packets of very small size to minimize packetization delay, causing very inefficient use of network bandwidth. This paper proposes a multiplexing scheme for improving the bandwidth efficiency of existing VoIP applications. By installing a multiplexer in an H.323 proxy, voice packets from multiple sources are combined into one IP packet for transmission. A demultiplexer at the receiver-end proxy restores the original voice packets before delivering them to the end-user applications. Results show that the multiplexing scheme can increase bandwidth efficiency by as much as 300%. The multiplexing scheme is fully compatible with existing H.323-compliant VoIP applications and can be readily deployed.Index Terms-Internet telephony, multiplexing, voice over IP.

Multiplexing VOIP Packets Over Internet Telephony Transport Protocol (ITTP)

“…However, a compression technique was applied on the RTP header. Implementation of the proposed technique showed that combining both packets multiplexing and RTP header compression succeeded in improving bandwidth utilization, whereas, bandwidth employment improved by 72% [9].…”

Influence of online games traffic multiplexing and router buffer on subjective quality

“…Other proposals for multiplexing RTP flows are [7] and [8]. They are mainly designed for VoIP, since this is a very popular service with a high overhead.…”

A multiplex-multicast scheme that improves system capacity of voice-over-IP on wireless LAN by 100%

“…Our compression is similar to the scheme proposed in [13]. It depends on the use of context-mapping tables in MUX and DEMUX to record necessary information such as RTP header for future reconstruction, source IP address for differentiation between VoIP sessions, synchronization for proper (de)compression and (de)multiplexing.…”

“…With this scheme, the RTP+UDP+IP header can be replaced with a 2-byte miniheader for most voice packets. We refer the reader to [13] for details. The major reason for the improved efficiency of our system here is the MUX/DEMUX scheme rather than the header compression scheme.…”