cs 241 section (11/18/2010)
DESCRIPTION
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) - PowerPoint PPT PresentationTRANSCRIPT
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CS 241 Section(11/18/2010)
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In Section Today…
• MP7
• Networking
• File System Intro
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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
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MP7
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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
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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
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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?
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Networking Review
• Would TCP or UDP be best to be used for…– Streaming Audio/Video?
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Networking Review
• Would TCP or UDP be best to be used for…– Streaming Audio/Video? UDP– Instant Messaging?
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Networking Review
• Would TCP or UDP be best to be used for…– Streaming Audio/Video? UDP– Instant Messaging? TCP– Simple File Transfer?
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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
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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
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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.
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MP8
• Broad Topic:– Make a web server!
• Programming Concepts Used:– Socket Programming– Multi-threaded Programming
• More on it in section in two weeks…
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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
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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.
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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
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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
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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)
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UNIX File Systems Introduction
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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