ABSTRACT
The background of the work presented in this dissertation is the
SUPANET (Single physical layer User-Platform (U-platform) Architecture
NETwork) introduced by Sichuan Network Communication Key Laboratory
(SC-Netcom Lab) to meet the needs of QoS for future merged networks. The
SUPANET simplifies the user-data transfer platform (U-platform) into a single
physical layer, which can greatly improve efficiency as well as QoS
provisioning for user data in the U-platform while remains interoperable with
existing Internet.
This dissertation focuses on adaptation issues between user traffic and the
basic data units (i.e. EPF - Ethernet-like Physical Frame) of the SUPANET
with regard to QoS requirements (throughput, transit delay, jitter, data loss rate,
etc.), data formats and lengths in the U-platform of SUPA. In order to provide
a systematic approach towards adaptation functions, this thesis defines
2-sublayer architecture for the SAL, SAR (Segmentation And Reassembly)
sublayer at the bottom and CS (Convergence Sublayer) at the top.
In view of application traffic can be classified into three groups on the
basis of nature of application traffic:CBR-T (Constant Bit Rate Time critical)
data flow、VBR-T (Variable Bit Rate Time critical) data flow and C/VBR-N
(Constant/Variable Bit Rate Non-time critical) data flow, three adaptation
protocols have been defined in the author’s work, they are:
A. SAL1 for CBR-T to ensure high data rate, low latency and jitters
B. SAL2 for VBR-T to with less critical constraints on traffic delivery but
with minimal error checking facility.
C. SAL3 for C/VBR-N with an emphasis on reliable data delivery.
Because CBR-T data flow requests transfers delay and jitter as little as
possible, SAL1segments user data and encapsulates Physical Frame,
appending nothing for user data. The reason for definition of SAL1 is that the
Bit Error Rate has been reduced to 10
-10
~10
-12
with continuous improvement
in communication technique and CBR-T data flow is not sensitive to
instantaneous data error. Due to the transfer’s less delay and reliability
requirements of such streams, SAL2 PDU provides length and CRC fields to
satisfy requirements of transfer. C/VBR-N data flow, which is non-time
