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Packet size distribution comparison between Internet links in 1998 and 2008
IPv4 packet size comparison for datasets in 1998 and 2008. Also compares IPv4 and IPv6 packet sizes in 2008. If you can contribute other data, please contact us at

Dataset characterization

dataset link type location date duration number of packets
FIX-west OC3 Fix-west exchange point 1998-03-12
(7m 15s)
IPv4: 5.7 M
Equinix-Chicago OC192 (only westbound direction) Link between Chicago, IL and Seattle, WA 2008-03-19
(1h 2m)
IPv4: 1.75 G
IPv6: 76 k
WIDE MAWI Samplepoint-F 150 Mbps Transpacific 2008-03-17 - 2008-03-21
(3d 15m)
IPv4: 3.82 G
IPv6: 11 M

Cumulative IPv4 packet size distribution in 1998 and 2008

Cumulative IPv4 packet size distribution by packets (solid lines) and bytes (dotted lines) for 1998 (Fix-West, an exchange point in California), and 2008 (Chicago exchange point and WIDE MAWI research backbone) data sets. Compared to the 1998 data, in 2008 the fraction of large ( > 1400 bytes ) packets has grown, while the fraction of small ( < 100 bytes ) packets has not changed much. The mode around 552 and 576 bytes from 1998 has largely disappeared in 2008.

Cumulative IPv4 and IPv6 packet size distribution in 2008

Cumulative IPv4 and IPv6 packet size distribution by packets (solid lines) and bytes (dotted lines) for Equinix-Chicago and WIDE MAWI research backbone, both taken in 2008. Notes:

  • The fraction of small IPv6 packets is very large. We speculate that many of the small packets are related to testing of ipv6-connectivity (e.g. icmp), with as yet little real content delivery happening over ipv6.
  • The RFC2460 IPv6 minimum MTU of 1280 is visible on the Equinix-Chicago link, but not on the WIDE link.
  • The IPv6/IPv4 ratio on the Equinix-Chicago link was 4.34e-05 and on the WIDE link 2.2e-03.
  • The Equinix-Chicago IPv6 dataset is arguably too small (76 thousand packets) to be representative.
  • Other IPv6 packet sizes that stand out: 552, 562 (eq-chic), 516, 752 (wide).

Common packet lengths

IPv4+TCP+512 MSS default for some implementations552 (512+20+20)
IPv4 Internet Path MTU (RFC 879)576
IPv6 minimum MTU (RFC1883)576
IPv6 minimum MTU (RFC2460)1280
Ethernet (RFC 1191)1500

Other packet size distribution studies

  Last Modified: Mon Jun-14-2010 11:06:31 PDT
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