Mobile Wireless Internet Forum Assesses IP Viability in Radio Access Networks for 3G Systems, Concludes IP Comparable to ATM for Transport Layer

FREMONT, Calif. - The Mobile Wireless Internet Forum's (MWIF) Technical Committee today announced that one of its working groups, IP in the Radio Access Network (IP in the RAN) completed work on MWIF Technical Report MTR-006.

The IP in the RAN Working Group 4 (WG4) concluded its work on the "IP in the RAN as a Transport Option in 3rd Generation Mobile Systems MWIF Technical Report" in early January. The report is the result of a 9-month feasibility study of Internet Protocol as a transport network option within two current and evolving 3G mobile systems: RAN and UTRAN (Universal Terrestrial Radio Access Network).

WG4 Chairman James Kempf highlighted the group's major conclusion that IP as a transport layer works as well or better than the R99-standard ATM

"The IP in the Ran working group assessed whether IP could be used in the 3GPP R99 UTRAN. The conventional wisdom was that IP transport on E1/T1 with HDLC framing would not have the necessary delay, jitter and bandwidth to compete with ATM transport," said Kempf. "Because operators prefer to use E1/T1 and other layers for their lower cost and greater flexibility, our study assumed that the existing UTRAN architecture and radio control protocols remain unchanged, with IP introduced for the transport layer only, in place of the ATM layer specified in the R99 standard.

"The results of the study show that with the proper combination of multiplexing and compression, IP is fully comparable with ATM for handling expected loads," noted Kempf, who is also a Senior Staff Engineer at Sun Microsystems (NASDAQ: SUNW). "As a result of this feasibility study, 3GPP has formed an ad hoc group examining how IP as the transport layer can be introduced into the next UTRAN standard."

UTRAN is being developed by 3GPP (Third Generation Partnership Project) for FDD and TDD modes. The IP transport option will be supported in the 3GPP2 (Third Generation Partnership Project II) open Abis specification (currently being balloted) and a future release of the 3GPP2 Interoperability specification (IOS v4.2 or a later version). As a transport option in RAN systems, IP benefits include cost reduction, deployment flexibility and scalability.

The WG4 report, which includes technical assessments, applicable IP stacks, RAN traffic models, and simulation results for IP delay and performance for several proposed IP stacks, resulted in several unanimous MWIF conclusions:

• IP in the RAN with careful design is a viable option, in particular, as it relates to delay and bandwidth efficiency concerns.
• Simulations conducted by several companies consistently demonstrated that the IP transport performance is equal or better than the present transport used in the RAN today. Based on the models described in MTR-006, IP transport showed approximately 10% improvement over ATM/AAL2.
• The bandwidth efficiency improvement of 10% for IP transport over AAL2 transport is a maximum value, which is only achieved over the last hop when no routing header is applied.

WG4 is continuing its evaluation of the IP protocol stacks with the goal of influencing the industry to adopt IP transport in the RAN. The application of IP may also be considered for other mobile systems, particularly where sharing of a common transport network between 3G mobile and other mobile systems might be considered to provide benefits to operators.
 

About Mobile Wireless Internet Forum

The Mobile Wireless Internet Forum (MWIF) was founded in January 2000, as a nonprofit mutual benefit corporation under California law. MWIF's mission is to drive acceptance and adoption of a single mobile wireless and Internet architecture that is independent of the access technology. MWIF and its working groups will publish studies, discoveries and conclusions in future reports. Membership is open to any organization with an interest in promoting the Forum's mission. Membership information can be found on the Forum's website at mwif.org.