4.2 Constraints

4.2.1 Performance Constraints

Since the aim of FCM is to ascertain whether the Client's algorithm is feasible, it is more of an experimental system, where performance is less critical. Hence, the only performance constraints on FCM are as follows:

• The Router kernel module of FCM must be able to modify packets (as described in Functional Requirements, section 3.1) at a rate of one megabyte per second for one minute.
• The Receiver kernel module of FCM must be able to receive packets (as described in Functional Requirements, section 3.1) at a rate of one megabyte per second for one minute.
• These two performance constraints must be measured on an Intel Pentium 4 processor, with a speed of two gigahertz, or an older Intel processor of lower speed.

4.2.2 Design & Implementation Constraints

FCM must:

• Contain modules for the standard Linux kernel version 2.4.18
• FCM must require no modifications to existing Linux 2.4.18 kernel code.
• Implement the TCP window size algorithm on the Receiver, as specified in the Client's paper in section 11.
• Be implemented using the C programming language.

SAM must:

• Run under Debian 3.0 (woody)
• Be provided as a Debian package, with any dependencies listed in the package
• Not depend on packages outside of Debian 3.0 unless provided to the user along with the package for SAM

4.2.3 Hardware Constraints

• The user must have a processor capable of running the Linux kernel 2.4.18.
• This PC must also have access to a network.