OIT Networking & Monitoring Services

Default IP Routers, Network Masks, and Broadcast Addresses

Most devices attached to the campus network learn the IP address of their default IP router (a.k.a "gateway"), the IP network mask (a.k.a. "subnet mask", or "netmask"), and the IP broadcast address via OIT DHCP and BootP Services. Those attached to some of the wireless networks operated by OIT learn this information via another specialized DHCP service operated by OIT.

If your device does not use DHCP or BootP (or those services are not available on the network to which your device is attached), you may use this table to learn the these values, so you may manually configure your device with this information.

In the first column, locate the range of IP addresses that include the IP address already assigned to your computer. In the second column, you will find the appropriate default router IP address. In the third column you will find the network mask, and the fourth column shows the broadcast address.

For example: if your IP address is 128.112.177.234, then the IP address of the default IP router is 128.112.176.1, the network mask is 255.255.252.0, and the broadcast address is 128.112.176.0.

This document does not include information for External Customer Networks. For IP ranges, network masks, and default IP routers for those networks, see External Customer Network Assignments.

If Your IP Address Starts With... Default IP Router
("gateway")
Network Mask
("netmask")
Broadcast Address
10.6.{0-15} 10.6.0.1 255.255.240.0 10.6.0.0
10.6.{16-31} 10.6.16.1 255.255.240.0 10.6.16.0
10.6.{32-47} 10.6.32.1 255.255.240.0 10.6.32.0
10.6.{48-51} 10.6.48.1 255.255.252.0 10.6.48.0
10.6.{52-53} 10.6.52.1 255.255.254.0 10.6.52.0
10.6.54 10.6.54.1 255.255.255.0 10.6.54.0
10.6.55 10.6.55.1 255.255.255.0 10.6.55.0
10.6.56 10.6.56.1 255.255.255.0 10.6.56.0
10.6.57 10.6.57.1 255.255.255.0 10.6.57.0
10.6.59.{0-15} 10.6.59.1 255.255.255.240 10.6.59.0
10.6.59.{16-31} 10.6.59.17 255.255.255.240 10.6.59.16
10.6.59.{32-47} 10.6.59.33 255.255.255.240 10.6.59.32
10.6.59.{48-63} 10.6.59.49 255.255.255.240 10.6.59.48
10.6.59.{64-79} 10.6.59.65 255.255.255.240 10.6.59.64
10.6.59.{80-95} 10.6.59.81 255.255.255.240 10.6.59.80
10.6.59.{96-111} 10.6.59.97 255.255.255.240 10.6.59.96
10.6.59.{112-127} 10.6.59.113 255.255.255.240 10.6.59.112
10.6.59.{128-143} 10.6.59.129 255.255.255.240 10.6.59.128
10.6.59.{144-159} 10.6.59.145 255.255.255.240 10.6.59.144
10.6.59.{160-175} 10.6.59.161 255.255.255.240 10.6.59.160
10.6.59.{176-191} 10.6.59.177 255.255.255.240 10.6.59.176
10.6.59.{192-207} 10.6.59.193 255.255.255.240 10.6.59.192
10.6.59.{208-223} 10.6.59.209 255.255.255.240 10.6.59.208
10.6.59.{224-239} 10.6.59.225 255.255.255.240 10.6.59.224
10.6.60.{128-191} 10.6.60.129 255.255.255.192 10.6.60.128
10.6.60.{192-255} 10.6.60.193 255.255.255.192 10.6.60.192
10.6.61 10.6.61.1 255.255.255.0 10.6.61.0
10.6.62 10.6.62.1 255.255.255.0 10.6.62.0
10.6.63.{32-63} 10.6.63.33 255.255.255.224 10.6.63.32
10.6.63.{64-95} 10.6.63.65 255.255.255.224 10.6.63.64
10.6.63.{96-127} 10.6.63.97 255.255.255.224 10.6.63.96
10.254.{0-127} 10.254.0.1 255.255.128.0 10.254.0.0
10.254.248 10.254.248.1 255.255.255.0 10.254.248.0
10.254.249 10.254.249.1 255.255.255.0 10.254.249.0
10.254.250 10.254.250.1 255.255.255.0 10.254.250.0
10.254.251 10.254.251.1 255.255.255.0 10.254.251.0
10.254.252.{128-131} (note 2) 255.255.255.252 10.254.252.128
10.254.252.{132-135} (note 2) 255.255.255.252 10.254.252.132
10.254.252.{136-139} (note 2) 255.255.255.252 10.254.252.136
10.254.252.{140-143} (note 2) 255.255.255.252 10.254.252.140
10.254.252.{144-147} (note 2) 255.255.255.252 10.254.252.144
10.254.252.{148-151} (note 2) 255.255.255.252 10.254.252.148
10.254.252.{152-155} (note 2) 255.255.255.252 10.254.252.152
10.254.252.{156-159} (note 2) 255.255.255.252 10.254.252.156
10.254.252.{160-163} (note 2) 255.255.255.252 10.254.252.160
10.254.252.{164-167} (note 2) 255.255.255.252 10.254.252.164
10.254.252.{168-171} (note 2) 255.255.255.252 10.254.252.168
10.254.252.{172-175} (note 2) 255.255.255.252 10.254.252.172
10.254.252.{176-179} (note 2) 255.255.255.252 10.254.252.176
10.254.252.{180-183} (note 2) 255.255.255.252 10.254.252.180
10.254.252.{184-187} (note 2) 255.255.255.252 10.254.252.184
10.254.252.{188-191} (note 2) 255.255.255.252 10.254.252.188
10.254.252.{192-195} (note 2) 255.255.255.252 10.254.252.192
10.254.252.{196-199} (note 2) 255.255.255.252 10.254.252.196
10.254.252.{200-203} (note 2) 255.255.255.252 10.254.252.200
10.254.252.{204-207} (note 2) 255.255.255.252 10.254.252.204
10.254.252.{208-211} (note 2) 255.255.255.252 10.254.252.208
10.254.252.{212-215} (note 2) 255.255.255.252 10.254.252.212
10.254.252.{216-219} (note 2) 255.255.255.252 10.254.252.216
10.254.252.{220-223} (note 2) 255.255.255.252 10.254.252.220
10.254.252.{224-239} 10.254.252.225 255.255.255.240 10.254.252.224
10.254.252.{240-255} 10.254.252.241 255.255.255.240 10.254.252.240
66.36.{60-63} (note 13) (note 13) (note 13)
66.180.176 66.180.176.1 255.255.255.0 66.180.176.0
66.180.177 66.180.177.1 255.255.255.0 66.180.177.0
128.112.{4,5,6,7} 128.112.4.1 255.255.252.0 128.112.4.0
128.112.{8,9} 128.112.8.1 255.255.254.0 128.112.8.0
128.112.12.{8-15} 128.112.12.9 255.255.252.248 128.112.12.8
128.112.12.{32-39} 128.112.12.33 255.255.252.248 128.112.12.32
128.112.12.{56-59} 128.112.12.57 255.255.252.252 128.112.12.56
128.112.12.{80-95} 128.112.12.81 255.255.252.240 128.112.12.80
128.112.12.{96-111} 128.112.12.97 255.255.252.240 128.112.12.96
128.112.12.{112-127} 128.112.12.113 255.255.252.240 128.112.12.112
128.112.12.{144-159} 128.112.12.145 255.255.252.240 128.112.12.144
128.112.{16,17,18,19} 128.112.16.1 255.255.252.0 128.112.16.0
128.112.{20,21,22,23} 128.112.20.1 255.255.252.0 128.112.20.0
128.112.{24,25,26,27} 128.112.24.1 255.255.252.0 128.112.24.0
128.112.{28,29,30,31} 128.112.28.1 255.255.252.0 128.112.28.0
128.112.{32,33,34,35,36,37,38,39} 128.112.32.1 255.255.248.0 128.112.32.0
128.112.{40,41,42,43,44,45,46,47} 128.112.40.1  (note 4) 255.255.248.0   (note 4) 128.112.40.0   (note 4)
128.112.{48,49,50,51} 128.112.48.1 255.255.252.0 128.112.48.0
128.112.{52,53} 128.112.52.1 255.255.254.0 128.112.52.0
128.112.{56,57,58,59} 128.112.56.1 255.255.252.0 128.112.56.0
128.112.61 128.112.61.1 255.255.255.0 128.112.61.0
128.112.62 128.112.62.1 255.255.255.0 128.112.62.0
128.112.63 128.112.63.1 255.255.255.0 128.112.63.0
128.112.{64,65,66,67,68,69,70,71} 128.112.64.1 255.255.248.0 128.112.64.0
128.112.{72,73,74,75,76,77,78,79} 128.112.72.1 255.255.248.0 128.112.72.0
128.112.{80,81,82,83} 128.112.80.1 255.255.252.0 128.112.80.0
128.112.{84,85,86,87} 128.112.84.1 255.255.252.0 128.112.84.0
128.112.{88,89,90,91} 128.112.88.1 255.255.252.0 128.112.88.0
128.112.{92,93,94,95} 128.112.92.1 255.255.252.0 128.112.92.0
128.112.{96,96,97,99} none   (note 2) 255.255.252.0 128.112.96.0
128.112.100.{0-127} 128.112.100.1 255.255.255.128  (note 8) 128.112.100.0
128.112.101.{0-15} 128.112.101.1 255.255.255.240 128.112.101.0
128.112.102 128.112.102.1 255.255.255.0 128.112.102.0
128.112.{108,109,110,111} 128.112.108.1 255.255.252.0 128.112.108.0
128.112.{104,105,106,107} 128.112.104.1 255.255.252.0 128.112.104.0
128.112.{112,113,114,115} 128.112.112.1 255.255.252.0 128.112.112.0
128.112.{116,117,118,119} 128.112.116.1 255.255.252.0 128.112.116.0
128.112.{120,121,122,123,124,125,126,127} 128.112.120.1 255.255.248.0 128.112.120.0
128.112.{128,129,130,131,132,133,134,135} 128.112.128.114 255.255.248.0   (note 7) 128.112.128.0
128.112.{136,137,138,139} 128.112.136.1 255.255.252.0 128.112.136.0
128.112.{140,141,142,143} 128.112.140.1 255.255.252.0 128.112.140.0
128.112.{144,145,146,147} 128.112.144.1 255.255.252.0 128.112.144.0
128.112.{148,149,150,151} 128.112.148.1 255.255.252.0 128.112.148.0
128.112.{152,153,154,155} 128.112.152.1 255.255.252.0 128.112.152.0
128.112.{156,157,158,159} 128.112.156.1 255.255.252.0 128.112.156.0
128.112.{160,161,162,163} 128.112.160.1 255.255.252.0 128.112.160.0
128.112.{164,165,166,167} 128.112.164.1 255.255.252.0 128.112.164.0
128.112.{168,169,170,171} 128.112.168.1 255.255.252.0 128.112.168.0
128.112.{172,173,174,175} 128.112.172.1 255.255.252.0 128.112.172.0
128.112.{176,177,178,179} 128.112.176.1 255.255.252.0 128.112.176.0
128.112.{184,185,186,187,188,189,190,191} 128.112.184.1   (note 5) 255.255.248.0   (note 5) 128.112.184.0   (note 5)
128.112.{192,193,194,195} 128.112.192.1 255.255.252.0 128.112.192.0
128.112.{196,197,198,199} 128.112.196.1 255.255.252.0 128.112.196.0
128.112.{200,201,202,203,204,205,206,207} 128.112.200.1   (note 3) 255.255.248.0   (note 3) 128.112.200.0   (note 3)
128.112.{208,209,210,211,212,213,214,215} 128.112.208.1 255.255.248.0   (note 6) 128.112.208.0
128.112.{216,217,218,219,220,221,222,223} 128.112.216.1 255.255.248.0 128.112.216.0
128.112.{224,225,226,227} 128.112.224.1 255.255.252.0 128.112.224.0
128.112.{228,229,230,231} 128.112.228.1 255.255.252.0 128.112.228.0
128.112.{232,233,234,235} 128.112.232.1 255.255.252.0 128.112.232.0
128.112.{240,241,242,243} 128.112.240.1 255.255.252.0 128.112.240.0
128.112.{252,253,254,255} 128.112.252.1 255.255.252.0 128.112.252.0
140.180.{128-191} 140.180.128.1 255.255.192.0 140.180.128.0
140.180.219.{128-255} 140.180.219.129 255.255.255.128 140.180.219.128
140.180.{220-221} 140.180.220.1 255.255.254.0 140.180.220.0
140.180.223.{128-159} 140.180.223.129 255.255.255.224 140.180.223.128
140.180.{224-231} 140.180.224.1 255.255.248.0 140.180.224.0
172.18.{0-15} 172.18.0.1 255.255.240.0 172.18.0.0
172.18.{32-47} 172.18.32.1 255.255.240.0 172.18.32.0
172.18.{64-95} 172.18.64.1 255.255.224.0 172.18.64.0
172.18.{128-143} 172.18.128.1 255.255.240.0 172.18.128.0
172.18.{192-207} 172.18.192.1 255.255.240.0 172.18.192.0
172.18.{224-255} 172.18.224.1 255.255.224.0 172.18.224.0
172.19.{0-15} 172.19.0.1 255.255.240.0 172.19.0.0
172.19.{64-67} 172.19.64.1 255.255.252.0 172.19.64.0
172.19.68 172.19.68.1   (note 11) 255.255.255.0 172.19.68.0
172.19.70 172.19.70.1 255.255.255.0 172.19.70.0
172.19.{72-75} none (note 2) 255.255.252.0 172.19.72.0
172.19.{80-95} none (note 2) 255.255.240.0 172.19.80.0
172.19.{96-111} none (note 2) 255.255.240.0 172.19.96.0
172.19.{128-159} none (note 2) 255.255.224.0 172.19.128.0
172.19.{160-191} none (note 2) 255.255.224.0 172.19.160.0
172.19.{192-255} 172.19.192.1   (note 12) 255.255.192.0 172.19.192.0
172.20.{0-7} none (note 2) 255.255.248.0 172.20.0.0
172.20.{16-23} none (note 2) 255.255.248.0 172.20.16.0
172.20.{32-39} 172.20.32.1 255.255.248.0 172.20.32.0
172.20.{48-63} 172.20.48.1 255.255.240.0 172.20.48.0
172.20.{64-71} none (note 2) 255.255.248.0 172.20.64.0
172.20.88 none (note 2) 255.255.255.0 172.20.88.0
172.20.{96-127} none (note 2) 255.255.224.0 172.20.96.0
172.20.{240-255} 172.20.240.1 255.255.240.0 172.20.240.0
192.168.2 none (note 2) 255.255.255.0 192.168.2.0
192.168.4.{0-15} 192.168.4.1 255.255.255.240 192.168.4.0
192.168.4.{16-31} none (note 2) 255.255.255.240 192.168.4.16
192.168.4.{32-63} 192.168.4.33 255.255.255.224 192.168.4.32
192.168.4.{64-127} none (note 2) 255.255.255.192 192.168.4.64
192.168.4.{128-191} none (note 2) 255.255.255.192 192.168.4.128
192.168.4.{192-207} none (note 2) 255.255.255.240 192.168.4.192
192.168.4.{208-223} none (note 2) 255.255.255.240 192.168.4.208
192.168.5.{32-63} none (note 2) 255.255.255.224 192.168.5.32
192.168.5.{64-127} none (note 2) 255.255.255.192 192.168.5.64
192.168.5.{212-215} none (note 2) 255.255.255.252 192.168.5.212
192.168.5.{216-219} none (note 2) 255.255.255.252 192.168.5.216
192.168.5.{220-223} none (note 2) 255.255.255.252 192.168.5.220
192.168.5.{224-255} none (note 2) 255.255.255.224 192.168.5.224
192.168.8 192.168.8.1 255.255.255.0 192.168.8.0
192.168.10 none   (note 2) 255.255.255.0 192.168.10.0
192.168.14 none   (note 2) 255.255.255.0 192.168.14.0
192.168.15 none (note 2) 255.255.255.0 192.168.15.0
192.168.{16-17} (note 9) (note 9) (note 9)
192.168.18 none   (note 2) 255.255.255.0 192.168.18.0
192.168.22 192.168.22.1 255.255.255.0 192.168.22.0
204.153.49 204.153.49.1 255.255.255.0 204.153.49.0

Notes

  1. There is no default IP router for this network; it is isolated, not routed to any other network.

  2. Prior to October 30 2001, the router address was 128.112.204.1, the subnet mask was 255.255.252.0, and the broadcast address was 128.112.204.0. Devices registered prior to that day and still manually configured to use the old router address and subnet mask would continue to function (with degraded performance) until December 2 2014, when support for the old values finally was retired.

  3. Prior to August 12 2003, the router address was 128.112.44.1, the subnet mask was 255.255.252.0, and the broadcast address was 128.112.44.0. Devices registered prior to that day and still manually configured to use the old router address and subnet mask would continue to function (with degraded performance) until December 2 2014, when support for the old values finally was retired.

  4. Prior to June 22 2005, the router address was 128.112.188.1, the subnet mask was 255.255.252.0, and the broadcast address was 128.112.188.0. Devices registered prior to that day and still manually configured to use the old router address and subnet mask would continue until December 2 2014, when support for the old values finally was retired.

  5. On the morning of November 1 2005, the IP subnet mask changed from 255.255.252.0 to 255.255.248.0. Customers were responsible for reconfiguring any devices that were manually-configured to use the new value.

  6. On the morning of July 18 2006, the IP subnet mask changed from 255.255.252.0 to 255.255.248.0. Customers were responsible for reconfiguring any devices that were manually-configured to use the new value.

  7. The subnet mask changed from 255.255.254.0 to 255.255.255.128 on April 26 2012.

  8. This network range is allocated to a private network; the customer responsible for it has further subnetting it and manages the address space and routers. Contact the customer responsible for the private network to determine an appropriate subnet mask, IP router, and broadcast address.

  9. The only network reachable via this router is 172.19.192.0/18. Devices multihomed on the Campus Data Network (CDN) and on this PPN network should configure a static route to 172.19.192.0/18 (network mask 255.255.192.0) via this router instead of configuring a default route via this router. (Configure a default router based on the device's Campus Data Network interface.)

  10. The only network reachable via this router is 172.19.68.0/24. Devices multihomed on the Campus Data Network (CDN) and on this PPN network may wish to configure a static route to 172.19.68.0/24 (network mask 255.255.255.0) via this router instead of a default route via this router. (Configure a default router based on the device's Campus Data Network interface.)

  11. These are External Customer Networks. For IP ranges, network masks, and default IP routers for those networks, see External Customer Network Assignments.


A service of OIT Networking & Monitoring Services
The Office of Information Technology,
Princeton University
Last updated: March 12 2015