CIS 3210 Lecture Notes - Lecture 12: Message Transfer Agent, Hostname, Simple Mail Transfer Protocol

• School: University of Guelph
• Department: Computing and Information Science
• Course: CIS 3210
• Professor: Xiaodong Lin

Document Summary

Value is hostname of the authoritative name server for this domain. Name is alias name for the canonical (the real) name. Value is name of mail server associated with name. No always on server, each host on the network can be both the client and server at the same time. No guarantee that any host is on, intermittently connected and changing ip addresses. Server transmission: must sequentially send n le copies: Time to send one copy = f / us (size / upload rate) N copies: n * f / us. Client: each client must download the le copy. Dmin = minimum (slowest) client download rate. The lower bound for time to distribute f to n clients using the client-server approach. Max upload rate (limiting max download rate) is us + ui. In other words, we now have multiple uploaders - the server and the clients that have chunks of the le.