Network Admin’s Guide to Synthetic Monitoring

As a network administrator, you are well acquainted with the Simple Network Management Protocol (SNMP), as well as a number of paid tools used to monitor private local and wide area networks. Monitoring traffic as it traverses the internet, however, is a different type of challenge -- one that can’t be monitored with SNMP. Instead, administrators must use other methods to isolate performance bottlenecks scattered across the vast and complex web of public network components known as the Internet.

Synthetic monitoring triangulates problems by testing performance and reachability from hundreds of vantage points. It also complements your Domain Name Service (DNS), Content Delivery Network (CDN), and Border Gateway Protocol (BGP) monitoring to provide a comprehensive perspective.

You can find a free, detailed technical explanation of DNS and CDN concepts in our guide to synthetic monitoring.

In this guide, we’ll cover the technologies that make the Internet tick, such as:

  • Internet Exchange Points (IXP)
  • Software Defined Wide Area Network (SD-WAN)
  • Border Gateway Protocol (BGP)
  • IP Transit

This guide also includes a list of sixteen free online tools available to help network engineers troubleshoot internet performance problems. The following diagram provides context for the concepts that will be covered in the  chapters that follow.

The Internet is made up of internet exchange points (IXP) and Autonomous Systems that exchange routes via the border gateway protocol (BGP)


Internet Exchange Point

In our overview article, you’ll learn about tiers of Internet Service Providers (ISP), Autonomous Systems (AS), and the Internet Exchange Points (IXP) ISPs use to exchange traffic via the BGP routing protocol. You’ll also be given some context for related technologies (such as SD-WAN and IPv6) and troubleshooting tools (such as ping and traceroute).

IP Transit

This chapter tackles the ISP arrangement known as “IP transit,” which is used to transport traffic to its destination, and understand how it differs from IP peering. You’ll also learn about supporting concepts like AS path, dual-homing, BGP communities, and Resource Public Key Infrastructure (RPKI), which helps protect against threats such as BGP leaks and hijacking


Software-defined wide area networks (SD-WAN) are the most popular way to connect remote corporate networks. In this article, we present the benefits and challenges of SD-WANs, and compare SD-WANs to dedicated connections based on the Multiprotocol Label Switching (MPLS) protocol.

BGP Attributes

Become versed in the inner workings of the Border Gateway Protocol by following diagrams and examples to understand BGP attributes, path selection algorithms, AS path, and Multi-exit discriminator (MED).

Online Network Tools

Put your newfound knowledge to use by accessing 16 free online tools. Each tool has a specific and useful functionality, such as testing website speeds from global locations, checking MX records, performing Organizationally Unique Identifier (OUI) lookups, browsing the most updated BGP route servers list on the internet, and more.

BGP Communities

Understand the purpose of using optional attributes known as communities in the Border Gateway Protocol (BGP) by learning the fundamental concepts, becoming familiar with the most common communities, and by seeing examples along with diagrams and router command line output.

Like what you’re reading?  We’re always adding new chapters to our guides, so stay tuned for more topics!


Learn the differences between Software-defined wide area networks (SD-WAN) and Multiprotocol Label Switching (MPLS) protocol in supporting your multi-site connectivity. In this article, we provide tabular side-by-side comparison, and explain the pros, cons and benefits of each solution.

MQTT Broker

Introduction page blurb: MQTT is a lightweight protocol that supports the Internet of Things (IoT). This article explains the functionality of its central hub known as the MQTT broker, compares its various implementations, and reviews its use cases, features, and best practices.

Inter-VLAN Routing

Learn why inter-VLAN routing is required, understand the different models used for implementing it, and follow examples to configure it.

DNS sinkhole

A DNS sinkhole is used to block malicious DNS requests. In this article, learn how the DNS sinkhole works, understand its limitations and best practices, and follow step by step instructions for setting it up.

How to Read a Traceroute

Learn how to run a traceroute command, interpret the results, and understand the common problems that it reveals.

Switching Loops

Understand how switching loops are created and learn the best practices for preventing them using the spanning tree protocol and portfast mode.