skip to primary navigationskip to content
 

Technical summary of port blocking for high-numbered incoming ports

If an institution has opted in to the scheme, tcp and udp packets with a destination port number in the range 1024-63999 will be rejected where they enter an institution's network from the CUDN, subject agreed exceptions by IP address or by port. The blocking is introduced in two stages:

  1. A period of monitoring is undertaken to determine whether the exceptions listed below will be adequate, or whether additional exceptions are needed.
  2. After agreeing the exceptions with the institution's IT staff, the blocking is activated.

Based on experience to date, the exceptions in the following table are used as a starting point for most institutions. The table may be updated in the light of further experience.

Destination
port/protocol
Source
port
Source
addresses
UseComment
any/tcp any any any only for established tcp connections
any/udp less than
1024
any any (e.g. response from nameservers)
6000/tcp
6001/tcp
any any X-windows
8008/tcp
8080/tcp
any any alternatives
for http
any/tcp 20 any ftp-data
any any 131.111.8.0/23
131.111.3.0/24
172.16.3.0/24
central servers
(incl. PWF)

Contact

If you have any enquiries regarding UIS network services, or other University network topics, please send an email to:

UIS Service Desk


  Phone padded  01223 332999

UIS Service Status

Phone padded  Service status line: (01223) 463085
Website  Sign up for SMS/email status alerts
Website  Read major IT incident reports

UIS bITe-size bulletin


A regular newsletter aimed at the University's IT community, highlighting service and project news from UIS.

Sign up >  |  Back issues

RSS Feed Latest news

UIS Christmas closure 24 December 2019 to 2 January 2020

Dec 13, 2019

UIS, including the UIS Service Desk and Reception in the Roger Needham Building will be closed for Christmas and New Year from Tuesday 24 December at 17:00. We will re-open on Thursday 2 January 2020 at 08:30. The Service Desk will also be closed, but we have an emergency contact in case you need one.

New system helps the University submit eligible staff to the REF

Dec 13, 2019

A new version of the REF Staff Information system was launched on 20 November, helping the REF team to ensure that eligible staff are submitted to the REF with correct and complete data. The project team adopted a unique approach to deliver the system on time under considerable pressure.

View all news