Route Explorer

BGP Root Cause Analysis

Network managers need better ways to identify and diagnose complex BGP issues affecting mission-critical Internet or inter-domain connectivity. Packet Design's breakthrough BGP Root Cause Analysis is a suite of capabilities that take what is often a flood of BGP protocol messages, and turns them into actionable analyses, including:

• Critical event notification: derived from detailed analysis of large volumes of BGP messages
• BGP policy verification: through snapshot-in-time visualizations of inter-AS routing
• Easily understood forensic analysis: including animations of changes in inter-AS routing over time

These capabilities significantly decrease mean time to repair (MTTR) and increase service uptime.

The Border Gateway Protocol (BGP) is the defacto inter-domain routing protocol used to manage complex interconnectivity. Despite its mission-critical role, networks based on BGP have traditionally been difficult to diagnose and troubleshoot because the number of routes being managed by BGP is large, generating thousands, even millions of updates following a significant peering loss or other adverse event. With today's large and complex networks, making sense of such large volumes of events is beyond human capacity. As a result, network operators are forced to react to customer complaints, rather than addressing issues proactively, before complaints surface.

BGP Root Cause Analysis equips network engineers with:

• An accurate view of inter-domain Layer 3 topology at any point in time
• Tools to analyze a virtually unlimited number of BGP events over any selected period of time
• The ability to isolate the few events that were the root cause of the BGP event stream

Key Features

History Navigator: Route Explorer provides a history navigator where network administrators can view a histogram of BGP routing events levels. Since Route Explorer records all the BGP routing updates, this historical viewer gives an accurate picture of BGP activity in the network at any moment in time. The history navigator also serves as "home base" for selecting time periods for further detailed and automated analysis.

BGP Root Cause Analysis: By selecting a time period in the history navigator and launching the Root Cause Analysis tool, the network administrator can see a summary of macro-level events and the number of BGP updates and prefixes associated with each event. This summary allows further exploration of the detailed list of events and prefixes associated with each event, as well as the option to view a dynamic animation of the macro-level BGP events in the selected timeframe.

BGP Root Cause Animation: The BGP Root Cause Animation feature shows a dynamic topology visualization of the macro-level dynamics that are indicated by the raw BGP event stream. Based on the timeline chosen, the user can play, slow-down, fast-forward, and rewind the animation to view how the multi-domain peering structures and routes changed over time. A multi-domain map and graphic representation of route volume per router peering provides insight into how external peers and next-hop peers have affected IBGP peers and overall routing behavior. Isolation of root-cause events such as peering flaps, MED (Multi Exit Discriminator) oscillations, misconfigured community tags and unwanted back-door paths is performed in minutes rather than days. This animation can be saved in SVG format and emailed to other providers, helping to coordinate inter-provider problem resolution. View application examples, including BGP Root Cause SVG animations.

BGP Static RIB (Routing Information Base) Visualizer: The BGP static RIB visualizer creates a visual snapshot that shows the tree of BGP routes including a numerical count and visual weighting of how many prefixes are carried by each routing branch. This view allows network engineers to view at a glance the behavior of BGP routing in the network, assess their routing policies and enable them to evaluate existing peering arrangements and plan future ones.

Key Benefits

Significant Reduction in Critical BGP Error Downtime: Critical BGP errors can have severe consequences because of the importance of Internet and inter-domain routing. Before Route Explorer, troubleshooting major BGP issues could take hours because of the sheer volume of routing updates. Using Route Explorer BGP Root Cause Analysis, costly and embarrassing downtime can be minimized and service availability maximized.

Proactive Service Assurance Analysis: Just as the high volume of BGP events tends to degrade network engineering's capability to troubleshoot critical errors, the ongoing high volume of events can disguise less critical but equally problematic BGP issues that may only manifest themselves in periodic service degradations. Without Route Explorer, these periodic service degradations can cause severe customer dissatisfaction because while the errors may occur periodically, they may not last long and will be difficult to track down because their symptoms are lost in the "noise" of the constant volume of BGP updates.

Since it is not uncommon for a large ISP to experience tens of thousands to hundreds of thousands of BGP updates per day, a single customers' BGP connection that is experiencing periodic problems can easily go undetected until the customer is very frustrated. Furthermore, without Route Explorer, costly dedicated equipment and personnel time may have to be dedicated to wait for the periodic issue to resurface multiple times before the problem can be resolved, adding to customer dissatisfaction. With Route Explorer, ongoing analysis of BGP phenomena in the network can be performed to ensure that no service affecting issues are eluding proper attention.

Network Optimization: BGP configurations provide a deluge of options for routes that are not easily understood given the high volumes of updates. Yet these options can have a dramatic effect on the efficiency and service availability of the network. With BGP Root Cause Analysis, network engineers can examine the state of their BGP routing such as:

• Consistency and effectiveness of current routing policies
• Whether EBGP peers are properly routing or if issues such as MED oscillations are creating undue load on routers in the network
• Existence of any backdoor routes or route leakage

Enhanced Inter-Domain Forensics: One of the most problematic issues facing both ISPs and large Enterprises when troubleshooting Internet routing issues is the lack of easily exchanged forensic data. Route Explorer BGP Root Cause Analysis allows one organization to capture multi-domain pictures and animations of BGP routing issues that indicates not only the nature of the problem but the routing domain where it arose. These pictures and animations can be saved and forwarded to other ISPs in SVG format to effectively communicate the issue.

Download "Meeting the BGP Management Challenge with Route Analytics" and other white papers

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© 2010. Packet Design Inc.