Networking and Telecommunications

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Networking and Telecommunications
15. Unix Networking
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Unix Networking

• X windows - gui interface (uses tcp/ip and
  network)
• tcp/ip - fundamental protocol used by unix
• internet - web servers, dns servers, bootp, etc..
  heavily based on unix systems (and
  nt/2000/novell)
• tcp/ip applications on unix - telnet, ssh, ftp,
  nfs/mount, ping, traceroute, web browsing, email
• /etc/hosts /etc/ethers (name, ip number,
  ethernet address)
• /etc/services (port numbers)

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/etc/hosts
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/etc/ethers
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/etc/services
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• NFS - Network File Systems - basic networking
• client - mount command
• mount server/directory /mountpoint
• server - share command
• All transparent to users - placed into files read
  at boot time.
• Does NOT use virtual drives - uses mount point
  (empty directory)

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NFS
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• Samba - software on the sun/unix server, that
  talks native Microsoft protocol, and allows pc's
  to communicate with unix server as if it were a
  nt/2000/2003 server.
• Used to communicate with our 95/98/2000/nt/XP pc
  clients, (H drive) in our labs

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Netstat

• gather network statistics/information, like
  number of input packets, number of output
  packets, collisions
• collision rate collisions / output
  packets x 100
• collisions rate lt 5 is good
• Full duplex fast ethernet on a switch should see
  zero collisions

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• ie.
• carp netstat -i
• Name Mtu Net/Dest Ipkts Ierrs Opkts
  Oerrs Collis
• le0 1500 carp.rutgers.edu 18979356 811
  12094590 160 456284
• Thus collision rate 456284/12094590 x 100
  3.7
• ping
• traceroute

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Ifconfig

• Gather network configuration information on local
  system, including ip address, Mac Address, subnet
  mask, broadcast address, etc..
• Example
• Clam ifconfig hme0
• Hme0 flagsltUP,Running,Multicast,IPv4)
• Inet 165.230.99.70 netmask ffffffc0
• broadcast 165.230.99.127 ether 8020d1d645

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• THE END!!