BGP Path Analyzer

Analyze BGP autonomous system paths for loops, prepending, and path information. Essential for BGP troubleshooting and network analysis.

Enter autonomous system numbers separated by spaces

Path Analysis

PATH LENGTH
4
LOOP DETECTED
✓ NO
ORIGIN ASN
AS65004
FORMATTED PATH
65001 → 65002 → 65003 → 65004

Autonomous Systems

AS #0
AS65001
AS #1
AS65002
AS #2
AS65003
AS #3
AS65004
ORIGIN
Private
UNIQUE ASes
4
ORIGIN INFO
Private AS number (not routable on Internet)

BGP AS Path

A BGP AS Path is the sequence of autonomous systems that an IP route has traversed from origin to destination.

Routers use AS path length as one of the metrics to determine the best path to a destination.

Path Attributes

Loop: ASN appears twice+
Prepending: Same ASN repeated
Length: Hop count
Origin: How route originated

Path Origins

i (IGP):From internal network
e (EGP):From external network
? (Incomplete):Learned from other protocol

ASN Ranges

1 - 64511: Public ASNs
64512 - 65534: Private ASNs
65535: Reserved