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CS 241 Section (11/18/2010). In Section Today…. MP7 Networking File System Intro. MP7. MP7 is due tonight is 11:59:59pm. Contest results based on due-date Usual late submission policy applies for grading purposes (30% off for up to 1 day late)
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In Section Today… • MP7 • Networking • File System Intro
MP7 • MP7 is due tonight is 11:59:59pm. • Contest results based on due-date • Usual late submission policy applies for grading purposes (30% off for up to 1 day late) • Contest results announced in-lecture on Friday (at beginning of lecture) • Must be in attendance to claim prize • Some nice prizes by Intel
Networking Review • Major TCP Benefits • Connect via a 3-way handshake • Reliable, ordered delivery • Single endpoint per connection • TCP: • Extremely useful protocol features • High Overhead
Networking Review • Major UDP Benefits • Stateless protocol • No connection, no pre-defined endpoint • Low overhead • No reliable delivery • No ordered delivery • Generally faster round trip time than TCP
Networking Review • TCP and UDP BOTH Provide: • IP Routing • Port-based delivery • The address “192.168.1.1:80” could refer to TCP or UDP. • Q: How do we know that address is likely TCP?
Networking Review • Would TCP or UDP be best to be used for… • Streaming Audio/Video?
Networking Review • Would TCP or UDP be best to be used for… • Streaming Audio/Video? UDP • Instant Messaging?
Networking Review • Would TCP or UDP be best to be used for… • Streaming Audio/Video? UDP • Instant Messaging? TCP • Simple File Transfer?
Networking Review • Would TCP or UDP be best to be used for… • Streaming Audio/Video? UDP • Instant Messaging? TCP • Simple File Transfer? TCP • Short, infrequent status updates of non-essential information? • BitTorrent Peer Updates • DNS, DHCP, etc
Networking Review • Would TCP or UDP be best to be used for… • Streaming Audio/Video? UDP • Instant Messaging? TCP • Simple File Transfer? TCP • Short, infrequent status updates of non-essential information? UDP • BitTorrent Peer Updates • DNS, DHCP, etc
MP8 • MP8 is scheduled to be released on Monday over break (Nov. 22nd) • The MP is designed as a one-week MP. • However, you have 2.5 weeks to work on it. • One week during break • One full week after break, and until Wednesday of the next week.
MP8 • Broad Topic: • Make a web server! • Programming Concepts Used: • Socket Programming • Multi-threaded Programming • More on it in section in two weeks…
UNIX File Systems Introduction • Nearly every modern file system is based on a directory structure: • / • /usr/ • /usr/kingst/ • /usr/kingst/svn/ • /usr/kingst/svn/mp7/ • /usr/kingst/svn/mp7/alloc.c
UNIX File Systems Introduction • Each and every directory contains at least two links to files: • /. A reference to itself. • /.. A reference to its parent. • Every other reference will be some form of a file or link.
UNIX File Systems Introduction • Information about the contents of a directory is stored in a directory file. • A directory file is simply a table containing two pieces of information: • The i-node ID of the file • The name of the file
UNIX File Systems Introduction • Information about the contents of a directory is stored in a directory file. • A directory file is simply a table containing two pieces of information: • The i-node ID of the file • The name of the file
UNIX File Systems Introduction • Much like many MP7 implementations, an i-node simply contains data about a file. • File size • Location (on disk) of the file’s contents • Modification date, creation date, etc. • File’s owner • File’s permissions • … • NOT THE NAME OF THE FILE (directory file)
UNIX File Systems Introduction • Main lecture will discuss more on i-nodes and file systems over the next week... • We’ll discuss i-node details next week