Mailbox Module
Role in the System
This module implements the transmission and reception of data across a network via the use of mail boxes. The relevant files are post.h and post.cc. When data is to be sent across the network, it first must be prepended with a mail header. In Nachos, this consists of information pertaining to:
- address of destination mail box
- address of sender mail box
- size of data in bytes
The mail header and data is then prepended itself with the packet header. Note that from the perspective of the packet, it does not distinguish between the mail header and data -- it is the responsibility of the receiving computer to parse the packet and extract the pertinent information. Furthermore, the mail box address and computer address are not the same; one computer could potentially have several mail boxes. The mail box address is used to identify which mail box on the destination computer the message is to be delivered to. The post office class manages the computer's mail box by sending messages or waits to retrieve them.
Uses Relation