An Investigation into Transport Protocols and Data Transport ...

1.4. Dissertation Outline 27
• Identification of Linux specific limitations upon TCP transport performance.
• Identification of ack and SACK processing bottlenecks on TCP transport
performance.
• The evaluation of single flow bulk transport over the Internet using
New-TCP algorithms.
• The identification of important network metrics for the successful utilisation
of TCP transport for Large Hadron Collider (LHC) applications,
with suggestions for New-TCP usage.
1.4 Dissertation Outline
Scope of the work in terms of the Large Hadron Collider (LHC) project
is presented in Chapter 2 and data replication requirements are discussed.
Preliminary tests are performed in Chapter 3 which investigates the performance
of the UDP and TCP protocols across the Internet. It is identified
that a performance gap exists between the two - suggesting that TCP has
performance problems not associated with raw hardware performance.
An in-depth review of TCP and the needs for congestion avoidance is
provided in Chapter 4 and the performance limitations are explored in Chapter
5. In particular, it is identified that the fundamental Additive Increase
Multiplicative Decrease (AIMD) congestion avoidance algorithm of TCP imposes
an absolute performance limit under realistic network conditions for
the High Energy Physics (HEP) research community.
A survey of amendments to the TCP congestion control algorithm is presented
and discussed in Chapter 6, a testing framework where new congestion