Nats network address translators
Download
1 / 5

nats network address translators - PowerPoint PPT Presentation


  • 235 Views
  • Updated On :

NATs (Network Address Translators). Henning Schulzrinne Dept. of Computer Science Columbia University Fall 2003. NATs. Network address translation = local, LAN-specific address space translated to small number of globally routable IP addresses Motivation: scarce address space

Related searches for nats network address translators

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'nats network address translators' - Rita


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Nats network address translators l.jpg

NATs (Network Address Translators)

Henning Schulzrinne

Dept. of Computer Science

Columbia University

Fall 2003


Slide2 l.jpg
NATs

  • Network address translation = local, LAN-specific address space translated to small number of globally routable IP addresses

  • Motivation:

    • scarce address space

      • cost: about $9k/year for up to 262,000 addresses

    • prevent home broadband users from running servers at home

    • security: prevent unsolicited inbound requests

    • avoid renumbering if provider changes

      • most small/mid-sized LANs inherit address space from ISP


Prevalence of nats l.jpg
Prevalence of NATs

  • Claim: 50% of broadband users are behind NATs

  • All Linksys/D-Link/Netgear home routers are NATs

  • Measurement: for Quake III users, about 17-25% using NAT (May/June 2001)


Nat details l.jpg
NAT details

  • RFC 1631 (first description)

  • RFC 1918 (private-use addresses)

  • RFC 2663

  • RFC 2776

  • RFC 3022

  • RFC 3027

  • RFC 3235

  • RFC 3424

  • RFC 3489 (STUN)


Nat types l.jpg
NAT types

  • All use net-10/8 (10.*.*.*) or 192.168/16 (172.16/12 also available)

  • Address translation

  • Address-and-port translation (NAPT)

    • most common form today, still called NAT

    • one external (global) IP address


ad