Project 1 wrapup Project 2 intro

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Project 1 wrapupProject 2 intro

• 15-441 Recitation 6
• By your always amazing Tas

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Outline

• Project 1 Wrap up
• Project 2 Intro
• Questions

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Project 1 Wrapup

• Congratulations!
• Youre done, regardless of your grade )
• What did you think of the following
• Difficulty
• Coding
• Documentation
• Our support

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Project 1 Our Feedback to You

• Pay attention to the assignments page
• Released checkpoints and scripts
• USE THE BBOARD -- SRSLY
• Its for your benefit
• If one TA is too busy to answer your question or
  not available, another can see it
• We are students too ?
• It helps others with your same question

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Project 1 Us to You Cont.

• Pay attention to who the lead TA is
• Takes care of the grading
• Who you should contact about late submission
• Your lead TAs
• Project 1 Jacob
• Project 2 David
• Project 3 George

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Project 2 IRC Routing Daemon

• WOAH! Thats super cool
• Youre right, more IRC (kind of!)
• Focus not really IRC anymore
• All about routing link-state
• You NEED a project parnter
• You may NOT work alone

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Finding a Project Partner

• This is very important, you will spend hours and
  hours with this person
• Start looking soon, inquire
• Class schedules
• Additional constraints research/work/life
• Hopes desires striving for 100? 80?
• Skills someone good at routing logic and someone
  good at coding?

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Post a Personal!

• Talk to students
• After class and in recitation
• 5 minutes to meet people here, right now, . YA
  RLY
• Additionally, mail the bboardHi, my name is
  George. My class schedule is XXXXX. I have a
  job and I work from X-Y on days A and B.

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IRC Servers and Routing
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New Definitions

• Node IRC server Routing Daemon
• nodeID unique node identifier
• Neighbor nodes A and B are neighbors if there
  is a virtual link between them
• Forwarding port same as IRC port
• Local port TCP port for server??daemon
• Routing port UDP port on daemon
• OSPF link-state protocol similar to the one
  youll be implementing
• Routing table used to store paths

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Link-state Routing Protocols

• Protocols with a global view of the network
• Every daemon knows about every daemon
• Every daemon knows connectivity graph
• Routing table constructed using shortest path
  tree
• Flooding is used to propagate routing informatoin

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LSA Link State Announcement
Version always 1 TTL initial(32) value--
every hop Type advertisement(0), ACK(1) sender
nodeID original sender sequence number per
LSA num ______ of entries Link entries
nodeID of neighbors User entries NICKs on
server Channel entries channels on server
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LSAs When to Generate

• Generate LSAs periodically
• Specified interval
• Generate LSAs on-demand
• User joins or quits
• First user on server to join a channel
• Neighbor is detected as down (timeout)

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LSA Propagation from nodeID 1
C
LSA
perl
LSA
perl C
perl C
C
perl
V(1), TTL(32), T(0) SEQ(50) snodeID(1) L(2),
U(0), C(1) 2 3 linux
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LSA Propagation from nodeID 1
LSA
LSA
LSA
C
perl
perl C
perl C
C
perl
LSA
LSA
V(1), TTL(32), T(0) SEQ(50) snodeID(1) L(2),
U(0), C(1) 2 3 linux
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LSA Propagation from nodeID 1
LSA
LSA
C
perl
perl C
perl C
C
LSA
perl
LSA
LSA
V(1), TTL(32), T(0) SEQ(50) snodeID(1) L(2),
U(0), C(1) 2 3 linux
Assume LSA from 2 got to node 5 before the LSA
from 3
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LSA Propagation from nodeID 1
C
perl
LSA
perl C
perl C
C
perl
V(1), TTL(32), T(0) SEQ(50) snodeID(1) L(2),
U(0), C(1) 2 3 linux
Assume LSA from 4 got to node 6 before the LSA
from 5
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Computing Routing Tables

• At every node
• Compute shortest past from every node to every
  node
• Create next hops table
• We will see in the following slides

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Understanding the Routing
PRIVMSG
C
perl
PERL ROCKS!
perl C
perl C
C
perl
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Understanding the Routing
C ROCKS!
PRIVMSG
PRIVMSG
PRIVMSG
C
perl
perl C
perl C
C
perl
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C
perl
perl C
perl C
C
perl
Node 1
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C
perl
perl C
perl C
C
perl
Node 2
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C
perl
perl C
perl C
C
perl
Node 5
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C
perl
perl C
perl C
C
perl
Node 6
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Server ?? Daemon Comm.

• Server and Daemon need to communicate
• Server notifies daemon of updates
• Networking details
• Server ?? Daemon TCP
• Daemon ?? Daemon UDP
• Dont panic, sample UDP code going to be released

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Server and Daemon Cmds

• Commands from server to daemon
• ADDUSER adds a user
• ADDCHAN adds a channel
• REMOVEUSER deletes a user
• REMOVECHAN deletes a channel
• NEXTHOP nodeID of next hop for target
• NEXTHOPS next hop, given a target
• USERTABLE user routing table
• CHANTABLE channel routing table

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Announcements

• The rest of the details are going to be in the
  handout
• Handout likely to be released today
• Homework 2 will be out today, due next Friday

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Questions?