Week 3: Application Layer Protocols

System call interface to sockets, DNS, HTTP, FTP, and email (SMTP, POP3, IMAP)

Lecture notes:
Application layer protocols - Lecture slides (6 per page)
Recitation notes:
Application layer protocols - email - Recitation slides (6 per page)
Terms with which you should be familiar:
Domain Name System, Internet Assigned Numbers Authority (IANA), Regional Internet Registry (RIR), generic Top-Level Domain (gTLD), country code Top-Level Domain (ccTLD), domain name registry, domain name registry operator, domain name registrar, shared registration, designated registrar, Domain Name System server, canonical name, authoritative name server, zone, root name server, iterative vs. recursive resolution, DNS resolver, referral, time to live, resource record, mail exchanger resource record, address resource record, canonical name (alias) resource record, name server resource record, DNS query, DNS response, reverse DNS, in-addr.arpa domain HTTP
HTTP, stateless protocol, uniform resource locator (URL), persistent vs. non-persistent HTTP connection, HTTP request/response, GET, POST, HEAD, uploading data, cookies, first party vs. third party cookies, HTTP caching proxy, conditional GET, ETag FTP
control and data channels, get, put, active vs. passive mode SMTP
Purpose, user agent, push vs. pull protocols, mail headers and their (non) relation to the SMTP protocol, MIME POP3
Purpose, types of commands, download-and-delete, download-and-keep, session state IMAP
Purpose, types of commands, folders