Skip to main content
HomeThe WWS Daily

- News, tips, inspiration you can trust to thrive in today’s digital age.

Search form

Main menu

  • Home
  • News & Features
  • Business & Economy
  • Tech & Trends
  • Health & Style
  • Arts & Culture
  • Contact Us

Understand BGP Routing in Computer Networking: Quick Guide

Hannah van Teylingen September 13, 2022

hannah-van-teylingen  Digital Marketing Specialist, Luden Digital. 

  WWS contributor info-icon.png

hor-z.png

Border Gateway Protocol (BGP) is essentially the Internet's postal service. This protocol aims at facilitating communication that is fast and efficient over the internet.

Understand BGP Routing in Computer Networking: Quick Guide

Border Gateway Protocol (BGP) is a protocol that allows data routing (the assignment of a path by which a message or data reaches its destination) to be made possible by the Internet. 

For example, BGP allows a US user to load a website with origin servers from the UAE. 

 

How BGP Works

 

Border Gateway Protocol (BGP) is essentially the Internet's postal service. This protocol facilitates communication that is fast and efficient over the internet.

The Postal Service receives mail dropped into a mailbox and determines the fastest route to send it to its intended recipient. Similarly, BGP routing reviews all available routes that data can take and chooses the best route. This method often means switching between autonomous systems (AS), which are a collection of devices or networks that share a common routing policy.

BGP is unlike the old Routing Information Protocol (RIP). This distance-vector routing protocol uses the hop count (which refers to the number of devices, usually routers, that a piece of data travels through) to determine routing metrics. 

To exchange routing information between two BGP systems (peers), a peering on both BGP speakers must be configured first. A peer will give you its complete data table at the beginning. Everything else is dependent on the updates received.

 

Route Updates

 

A routing table, or routing information base (RIB) in computer networking is a data table stored in a router or a network host that lists the routes to particular network destinations, and in some cases, metrics associated with those routes.

Routing information bases (RIB) are used to store route updates. Although a routing table can only store one route per destination, RIB usually has multiple possible routes to a destination. The router decides which routes to include in the routing table and which paths to use. If a route gets withdrawn, it gets rerouted from the RIB.

The RIB can only track routes that might get used. If a route withdrawal is received but does not exist in the RIB, it gets silently removed from the RIB. Peers are not notified of any updates. RIB entries never time out. They exist until it becomes apparent that the route got discontinued.

 

BGP Path Attributes

 

Many times, multiple routes will lead to the same destination. BGP routing uses path attributes to determine which route traffic should be directed to specific networks. The simplest of these is Shortest AS Path. The Shortest AS Path is the path that traverses the most AS "wins."

Multi_Exit_Disc, also known as Multi-exit discriminator or MED, is another critical attribute. The Multi_Exit_Disc allows remote AS to determine if there are multiple exit points to the network. If so, one exit point is preferred.

The Origin attribute provides information about the origin of a routing upgrade. BGP may have multiple routes. In that case, the origin will determine which route is preferred.

 

Problems Facing BGP

 

You need to discuss the Internet's problems to understand how BGP works. First, routing table growth is a significant problem. A person could start advertising hundreds more routes by disaggregating a network that was once a single /16 network.

When this happens, every router on the Internet will receive every new route. People continually pressure themselves to combine or aggregate multiple routes into one advertisement. It is not always possible to aggregate routes, especially if you need to split a /19 into two separate, geographically distinct /20s. Routing tables now have over 200,000 routes, and they appeared to be growing exponentially for a while.

The second concern is that "advertising the Internet" can be a problem. Suppose a large ISP customer decides to advertise, and the ISP allows the routes. In that case, all the traffic to the Internet's servers will be sent directly to the AS.

There is an easy solution. Route filtering is the solution. It's easy to set up filters that prevent routers from accepting routes from customers who you aren't expecting. However, large ISPs may still accept "default," equivalent to transit from peers.

 

Who Operates BGP Autonomous Systems?

 

Autonomous systems numbers (ASNs) are usually associated with Internet service providers (ISPs) or large organizations such as tech companies and universities, government agencies, scientific institutions, and universities. Every AS that wishes to exchange routing information must have an ASN (registered autonomous system number).

Internet Assigned Numbers Authority (IANA) assigns ASNs (ASNs) to Regional Internet Registries. These registries then assign them to ISPs or networks. 

ASNs can be 16-bit numbers between one and 65534 or 32-bit numbers between 131072 and 42949672944. There are 64,000 ASNs worldwide as of 2018. These ASNs can only be used for external BGP.

 

Difference Between Internal and External BGP

 

External BGP (eBGP) allows traffic to be sent over the Internet, exchanging routes. Autonomous systems can use an internal version of BGP to route through their networks. This internal version is called internal BGP (iBGP). 

Not using internal BGP to route through your internal networks is not a prerequisite for external BGP. An autonomous system can choose from many internal protocols to connect routers in its internal network.

Continuing with the Postal Services analogy, external BGP works in the same way as international shipping. International shipping of mail requires that you follow certain guidelines and standards. After the mail has reached its destination country, it must be sent through the local mail service of that country to reach its final destination.

Each country's internal mail service is different and may not follow the same guidelines. Like the above, each autonomous system may have a routing protocol for routing data within its network.

 

In Conclusion

 

BGP is an integral part of the Internet foundations. Because it must be manually configured, it is susceptible to human error as much as security attacks. Instabilities and service disruptions are becoming more common as networks evolve. 

In the context of global digital services, monitoring BGP behavior in terms of performance monitoring, path discovery, and path changes is critical.


Hannah van Teylingen is a Digital Marketing Specialist at Luden Digital.


 

 

SUBSCRIBE TO OUR NEWSLETTER  newsletter icon.png

Get our best content, news, tips, and inspiration in your inbox - free.

No spam. Just great stories. Promise!
 

 

Join Over 20,000 Subscribers!

Get our best content, tips, and inspiration free in your inbox. Subscribe ››

Connect with us:  twitter.gif linkedin-gray.jpg email.gif RSS feed

 

 

 

 

 

Most read this week


marketing-strategy-desktop-computer-workstation
9 Marketing Strategies & Trends Defining Success for Businesses
Anna Stella

4 Keys for Success As an Influencer
4 Keys for Success As an Influencer
Ekaterina Jimenez

Hacks to Develop a Morning Routine That Sets You Up for a Productive Day
Simple Hacks to Develop a Morning Routine That Sets You Up for a Productive Day
Evelyn Kail

woman_food_courier_in_uniform_carrying_food_in_paper_bag_and_takeaway
Different Types of Food Delivery Business Models & Platforms to Leverage Them
Archana Inani

 

Got a story or tip for us?

 

Tips_0_0_0.png

Here's how to submit it →

 

 

 

 

EXPLORE MORE ...

black-nav-bar1.png

News & Features  ›


man-independent-creator-spring-creators-campaign

Spring ‘FOR CREATORS’ Campaign to Elevate Independent Creators

Brexit Impact: Over 150,000 More Businesses Registered After the Referendum

Brexit Impact: Over 150,000 More Businesses Registered After the Referendum

Understand and Plan Your Digital Afterlife

Understand and Plan Your Digital Afterlife


The Most Annoying Video Call Habits at Work - Are You Guilty?

The Digital Playground: Creating Safe and Engaging Online Spaces for Kids

Understanding Fathers’ Rights in the Child Custody Process

hor-line-blue

Tech & Trends  ›


Key Tactics for Attracting & Retaining Tech Talent in Today’s Market

Key Tactics for Attracting & Retaining Tech Talent in Today’s Market

Best Mac Cleaners to Easily Achieve a Clean and Superfast Mac

Best Mac Cleaners for a Superfast Mac

Content Marketing Trends to Inform Your New Year Marketing Strategy


Understanding the Limitations of Antivirus Software

5 Web Accessibility Issues to Avoid

Ethics of Quality Assurance Tech Companies Need to Follow
 

hor_line_yellow

Arts & Culture  ›


Authorpreneurship: The Rise of Author-Led Publishing Houses

Authorpreneurship: The Rise of Author-Led Publishing Houses

Make Money Selling Digital Art

Make Money Selling Digital Art

woman-gazing-woods-perserverance

25 Powerful Quotes On Perseverance to Keep You Going


How Reading More Inspires Better Writing

10 Fun Hobbies & Activities for Couples to Enjoy Together

5 Ways to Make Writing a Lot More Fun

hor-line-brown

Business & Economy  ›


Must-Know Essentials for Digital Nomads Moving to Canada

Must-Know Essentials for Digital Nomads Moving to Canada

How to Protect Yourself from Skinwalkers. Yes, They May Be Real

Global Expansion: Top Tips to Expand Your Business Across the World

How to Break Into the Market As a New Freelance Writer (and Land Your First Jobs)


How Salesforce Anywhere Can Transform Remote Work With Real-Time Collaboration

Maximizing Device Compatibility with Restreaming and Packaging: Benefits for OTT Operators

Smooth Operator: 5 Daily Habits that Dramatically Reduce Repair Frequency

hor-line-green

Health & Style  ›


Woman_on_flight_smiling

Hacks to Upgrade (& Save On) Your Travel Experience

Traditional-Mexican-Home-Exterior-Style

Unlock the Magic of Mexican Style in Your Home Décor and Design

Pregnant at Work? Top Healthy Pregnancy Tips for Working Women

Pregnant at Work? Top Healthy Pregnancy Tips for Working Women

hori-3.jpg

Blissful Ways to Pamper Yourself at Low Cost

hori-3.jpg

7 Must-Haves for Hiking, Fishing, and Other Outdoor Activities

hori-3.jpg

The Different Types of Wine Explained in a Nutshell
 

Home | About Us | Contributors | Submissions | Advertise | Disclosure | Privacy Policy | Contact Us

Follow Us:

twitter_e.jpg linkedin-pg.jpg email-updates_icon.jpg

Committed to quality content and journalistic ethics.

RSS rss

Search WWS search-icon-trans_0_1.png

© 2025 The WWS Daily.