?
Solved

Why last ARPANET approach for setting link weights abandoned in the Internet

Posted on 2010-08-24
7
Medium Priority
?
63 Views
Last Modified: 2016-05-28
 In the ARPANET, link weights used to change dynamically. They represented the average delay over a period of 10 seconds. Whenever a link delay changed considerably, the router would issue a routing update to report the link weight change. Why was this approach for setting link weights abandoned in the Internet?
0
Comment
Question by:mrkidhiworld
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
  • 2
7 Comments
 
LVL 4

Accepted Solution

by:
DeadRatRacer earned 1336 total points
ID: 33549510
The current routing protocol, BGP does still use a metric weighting system that is affected by link speed and other factors like link stability.

Each AS participating in Internet routing sort of keeps its own view of the world and every route possible relative to itself, based on information from its neighbors that keep their own view based on ITS neighbors and so on.

For issues of scaling - directly notifying a backbone router in Brazil that a link in Nebraska many hops away is running a bit slow would not serve any meaningful purpose.

Out of curiosity, which specific version of ARPANET routing are you referring to? The system evolved over time and adjustments/changes happened many times in the evolutions that lead to the modern internet.
0
 
LVL 4

Assisted Solution

by:DeadRatRacer
DeadRatRacer earned 1336 total points
ID: 33549641
Small excerpt taken from
http://www.isoc.org/internet/history/brief.shtml


The increase in the size of the Internet also challenged the capabilities of the routers. Originally, there was a single distributed algorithm for routing that was implemented uniformly by all the routers in the Internet. As the number of networks in the Internet exploded, this initial design could not expand as necessary, so it was replaced by a hierarchical model of routing, with an Interior Gateway Protocol (IGP) used inside each region of the Internet, and an Exterior Gateway Protocol (EGP) used to tie the regions together. This design permitted different regions to use a different IGP, so that different requirements for cost, rapid reconfiguration, robustness and scale could be accommodated. Not only the routing algorithm, but the size of the addressing tables, stressed the capacity of the routers. New approaches for address aggregation, in particular classless inter-domain routing (CIDR), have recently been introduced to control the size of router tables.
0
 
LVL 4

Expert Comment

by:DeadRatRacer
ID: 33549651
And I neglected to mention before that alot of the metric re-jiggering is done by the network operators and less by the protocol itself
0
Get your Conversational Ransomware Defense e‑book

This e-book gives you an insight into the ransomware threat and reviews the fundamentals of top-notch ransomware preparedness and recovery. To help you protect yourself and your organization. The initial infection may be inevitable, so the best protection is to be fully prepared.

 
LVL 28

Assisted Solution

by:mikebernhardt
mikebernhardt earned 664 total points
ID: 33559621
BGP does not, and has never done, any automatic changes due to link speeds or other dynamic factors! A link is either up or it isn't. After that everything is determined by policies that have been configured by humans.

Dynamic changes are a function of IGPs like OSPF or EIGRP. EIGRP especially has the capability to change metrics based on factors like congestion (but no one uses it). The Internet is far too big, and therefore has far too many links, for tens of thousands of routers to be constantly updating routing tables due to metric changes somewhere. The whole Internet would come to a halt!
0
 

Expert Comment

by:EE_AutoDeleter
ID: 41620661
I've requested that this question be deleted for the following reason:

                           
No comment has been added to this question in more than 21 days, so it is now classified as abandoned and is now flagged for deletion.


If there is a valid solution, please OBJECT and indicate the comments that are, or would otherwise lead to, a solution.


Use the specific format http:#axxxxxxxx for comment ID(s).


Also, please don't object simply because the author did not respond to your comment. While we understand this is frustrating, unfortunately we cannot force the author to return to the question. Unless you feel you have presented a valid, verifiable solution we'll simply delete the question.


Experts-Exchange Auto Deleter
0

Featured Post

Free Tool: Subnet Calculator

The subnet calculator helps you design networks by taking an IP address and network mask and returning information such as network, broadcast address, and host range.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

We recently endured a series of broadcast storms that caused our ISP to shut us down for brief periods of time. After going through a multitude of tests, we determined that the issue was related to Intel NIC drivers on some new HP desktop computers …
Configuring network clients can be a chore, especially if there are a large number of them or a lot of itinerant users.  DHCP dynamically manages this process, much to the relief of users and administrators alike!
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
Suggested Courses

743 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question