GB7CIP Amateur Radio International Gateway.

Mail forwarding over AX25, NetRom, IP and SMTP  via HF PACTOR over
Amateur Radio Short Wave bands, VHF, UHF, amprnet wireless and internet links.

G4APL MaintainedUK AX25 BBS Listings 
G4APL MaintainedGB7CIP Forwarding (pdf)

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Network Management

As part of the movement to rebuild the amprnet AX25/TCPIP (IP over AX25) network across the country.
The following Linux Nodes and Connected AmateurPacketRadioNETwork systems are now active.

New Linux nodes England

SysOP NOV Callsign Location County Active
G0KUX GB7KUX Southgate North London Apr 2022
G0WDA   Blackpool Lancashire Sep 2022
G1GXB GB7SOU Southampton Hampshire < 1994
G0AOZ MB7NBA Bampton Oxfordshire < 1994
G3WEG GB7DOR Ferndown Dorset Oct 2021
G3ZFR GB7COV Corley West Midlands < 1994
G4APL GB7CIP Caterham on the Hill Surrey < 1994
G4TNU GB7IPF Amersham Buckinhamshire < 1994
G4VSS MB7NMI Warrington Cheshire Sep 2017
Not Active
Oct 2023
Welcome back
G6VEY   Bourne South Lincolnshire Feb 2018
G7OAH   Bicton East Cornwall Mar 2021
Not active
G7VJA GB7COW Hartland North Devon Aug 2016
M0JXM   Holloway London May 2019
Part time
M0NXP   Southamptom Hampshire Jan 2018
Part time
M0SKF GB7NWG Wood Green North London Mar 2018
Not Active
M6ORT   Southgate North London Feb 2017
2E1GW    Southgate North London Feb 2019
G0AOZ MB7NBA Bampton (XR IP Router) West Oxfordshire Feb 2017
Is this list complete?
73 de Paul G4APL

Reminder from the UK AMPRNet Co-Coordinator
This applies to all those Licence Radio Amateurs that use the new REVISED amprnet assigned Network addresses in the and Subnets effective from 19 July 2019.
Note assigned to the UK being subnet 44.131.#.#

You are reminded that you need to LOGIN to the portal at least ONCE per year.

(I Suggest at LEAST EVERY SIX MONTHS to be on the safe side de g4apl).

Check that your assigned subnet is still listed under the parent Network By selecting your subnet.

Failure to do so, the system will purge your account automatically.

Login to the AMPRNet portal via

The AMPRNet portal does send out reminders to the email address on the account after no activity after 6,9,12 months before purging, and an email will be sent confirming removal of account after 15 months of no activity.

Network Support and history
Paul has assisted and supported many of the SysOp's in the list and others not in the list above, in configuring their systems over the past 25 plus years.
Many of which have thanked him for sharing his networking and Linux knowledge, allowing them to advance in their technical careers.

Quote from Jack AA6HF May 2019
"Your gateway is the 'gold standard' that I always use to verify things are working."

Quote from Marco IW2OHX Nov 2020
"Hi Paul,
What a honor to do forwarding with your station GB7CIP!
GB7CIP represents the history of PacketRadio/Pactor and TCP/IP over radio.
I remember, I started first experiments with TCP/IP in 1993-94 with the NOS.
I was along with my brother Raffaello (IZ0QWM now, ex IW7CHV).
I was just a child, like my son now. I had fun playing with FTP, Telnet,

Quote from Jose Maria CX2SA April 2022
"Congratulations for your system.
Very solid and excellent BBS."

 More Feedback! May 2022
"You have my full support Paul, keeping the Caterham system secure.
I know. It’s a 24hr. 7 days a week. 52 week. 365 days a year job.
And some how, I don’t know how, you have the time to do family things
and do all your hobbies.
Well done and keep it up. 73."

Since the late 1980s Paul G4APL and Bryan G0SYR have been involved with Amateur Radio AX25, NetRom and later TCP/IP network management.

Liaising with new SysOp's and SysOp's around the London and Home Counties to ensure that the CatRad nodes (up to sixteen running the different versions of TheNet X1J up to X1J4 during the period 1988 to 2001)Each TNC X1J4 Stack were connected to one  'diode matrix' interface with one matrix Interface connected to the serial port of the PC/Server.
At GB7CR/GB7CIP there was two 5 port diode matrix Interfaces connected together
to make 8 interfaces available to connect the 6 PacCom Tiny2/Radios and the Server.

These were
over three sites GB7CP <19200baud 70cm link> GB7CR License 31 March 1990 (Caterham on the Hill Surrey) and <9600baud 70cm link> GB7HW (now closed 3 June 2001) near the M40 motorway Junction 5.  Enabling AX25 IP and NetRom linking to Didcot and radio paths to Coventry network and beyond.

They also had another 70cm 9600baud link to GB7IPC near M40 Junction 4.  Until that sysop Andy G4BIO became a Silent Key (SK). Providing ongoing links to the TCPIP Thames Valley Network.

GB7CP provided 70cm 9600baud
AX25/IP/NetRom RF links to Crawley, Littlehampton and or to Worthing. and a 70cm 1200baud link to Hastings.  Which had Radio links to Belguim carrying GB7CIP User Mail, Bulletins for EU BBS's two way forwarding feeds.

 2002, we ran all our TNCs (Terminal Node Controllers)  in Kiss mode with the JKiss eprom image installed  connected via one of 13 serial interfaces to a Linux Server (GB7CIP/GB7CR) or XRouter(GB7CP) node software.
Note: GB7CP closed 8 November 2014. GB7CR(operational 31.3.1990-5.3.2015) closed and relicenced as MB7NCR 6.3.2015

GB7CIP First licenced 29.1.1995 and developed to become The North East Surrey International amprnet Internet gateway.
Following the closure of a local GB7SRC AX25 BBS  in May 2003, added and took over AX25 BBS and Forwarding services.

We have based our network management, as had other efficient Node site SysOp's on the decisions made during the early Sysop meetings. Known as SYSOP5 and SYSOP6. 
That is we used route quality 120/255 gave a NetRom view of 5 node hops
and 100/255 gave a NetRom view of 4 node hops, with a Min quality of 10 and obs 6.
Using  broadcasts of 30,45 or 60 minutes. Still in use today in some UK network segments.

In our view this has worked very well for the UK for the past 30+ years

Paul G4APL has located some files on some old floppies with articles written by Mike Tubby G8TIC back In 1988/1989 which are applicable to todays new Node SysOp's around the UK and the rest of the world that are now experimenting with XRouter, LinBPQ, xnet, Linux built-in network infrastructure..

NetRom path routing qualities
SysOp's that run Node's that insist on using 230, 250, 255 path value for each route.  Are treating the world and one big logical stack of Terminal Node Controllers (TNC).   (250/255) (255/255
Hijacking the crafted routing table and br
eaking the NetRom network.

The High value automated system does not work  Hence a lot of the new sysops are 'insisting' on creating point to point UDP AX25 tunnels and not using the NetRom network correctly.

The result is that most
of the 600 to greater than 1000 nodes in a 'node table' are not connectable from the various nodes around the world. 
Due to the dynamic routing tables being broken, where SysOp's use very High Minimum quality values or INP3.(Internode Protocol) to limit the number of entries in their node tables.

Takes too long to broadcast per Interface.  Especially when they are being broadcast every 10 minutes

This requires a 'Network Managed Network SysOP'  to manually check and reduce the path values to a working value by using the node command . e.g.  N CALLSIGN-SSID and review the three path values.
Then make adjustment using the 'route command' Or refusing a an uninvited direct route linking automatic request to gb7cip by blocking the remote Source IPaddress in an up stream firewall if the remote system fails to reconfigure their system.

G4APL manages UK network systems initially with path value 100 or 120/255 (provides 4 or 5 NetRom hops) Where as USA (and others) use 192/255 or 203/255 with high minimum quality 160 to 200 (needs to be confirmed) to reduce the number of entries in their node tables.
For YOUR NODE link to be compatible with this system,
YOUR node Broadcasts are required to be set for every 30 minutes

Currently in 2017/21 there are XNet nodes that are broadcasting their node tables
every FIVE to TEN MINUTES containing well over 900 node entries down the GB7CIP Interfaces.
Yes some of us still use radio interfaces and even run IP over ax25 Radio links.
Surely there is no new node system being built and entering the network every five, ten or fifteen minutes.

This just generates a continuous node broadcast 24 hours a day,
Which is unnecessary and using up peoples paid for monthly ISP (Internet Service Provider) broadband download allowance.
Also incompatible and Not a good use of the ongoing radio interfaces that are linked.
Which are CONTINOUS!! Using up unnecessary Internet Broadband bandwidth.

Now G4APL is seeing unsolicited (uninvited) UDP links to gb7cip being established, sending their node broadcasts Ten Node blocks of node lists EVERY MINUTE for many months. or every 5 to 10 minutes.  (also with max path value of 255/255 from a Xnet/BPQ system)

Without consulting the sysop in advance and agreeing the UDP tunnel interface to be used, configured and agree path values depending on the Remote System Network Software being used to connect to gb7cip.

G4APL contact details are in the Public and amprnet 'space'  He won't bite!!

(InterNode Protocol)
Those systems that have the INP3 process timer routing tables enabled, will find that their system routing tables will have lots of nodes.
Most will be unconnectable and incompatible with the vanilla original NetRom protocol.

Note the vanilla NODES broadcasts are ignored, and any learned 'timed' routes will use INP3.
Command N T lists the 'timer linked nodes and N N will list the Vanilla NetRom Nodes
From a user perspective trying to make a connection will appear to fail to connect. due to unbalanced routing tables and the 'black holes generated by this process.

system does not support Internode Protocol (INP3) KEEPLI  (Keep Alive) and other similar systems.
Therefore (Lin)BPQ32
or XRouter systems that have agreed UDP tunnels to GB7CIP-5.

Are require to add a
Static Route to their Systems bpq.cfg. configurations. Therefore disabling INP3 on this link, to maintain reliability of their UDP tunnel link to GB7CIP-5's International Network Gateway.

The 192/255 is normally the def
ault path quality of a BPQ System.
under the sections
GB7CIP-5,192,<Your UDP port number e.g.> 2


te: adjustments are made to the obsolescent node values when using node broadcast less than every 60 minutes to be compatible with other systems.
60 Minutes Broadcasts Max Quality= 6 Min Quality=4 Default
30 Minutes Broadcasts Max Quality= 8 Min Quality=4 Default
20 Minutes Broadcasts Max Quality= 10 Min Quality=4 Default
10 Minutes Broadcasts Max Quality= 12 Min Quality=4 Default

Uses up too much bandwidth.  Especially for those SysOp's that have Internet Capped Bandwidth by their ISP.

Uses up too much memory on other SysOp's servers running different software.

NetRom Network Routing gets hi-jacked due to the 255/255 and INP3 timer path values.

Takes too long to broadcast over 1200 and 9600baud radio links

SysOp's should not need to use Minimum Quality values to limited the nodes in their node tables.  If they used sensible Routing Path Values.

The result of this.  Other SysOp's restrict the values to attempt to gain control
'the view' of their local network
As user should be able to connect to every node.  Listed in the node table.

Which is not the case today.

To test the
AX25 personal mail forwarding path to and from GB7CIP from anywhere in the world.
Send a ping message addressed as
Via AX25          SP PING@GB7CIP.#32.GBR.EU
Via amprnet

Management of UK network nodes By G8TIC December 1988/1989 

Xrouter Network Strategy by G0SYR December 2003
Xrouter Background Network Management View Point by G0SYR January 2004

as used back in 1986-2003

UK NetRom Node Radio Link Map    UK NetRom Radio & Internet Links Map (2005) most of these nodes have closed down as at 2013

During the 2005 UK Packet Conference held 7th May 2005 in Worcester. 
The SysOp's and Users present, agreed that a BBS Forwarding Paths and Active UK BBS  DataBase would be maintained.  To document how UK GB7### BBS's route Personal Messages around the UK and the rest of the world.

Information being supplied by UK BBS SysOp's.
Bryan G0SYR agreed to undertake this task
and has now been taken over by Paul G4APL.

The object of the exercise is:-
1) A central database of information that Users and BBS SysOp's can check who has current working  forwarding paths to Parts of the UK and the Rest of the World.

2) Prevent Personal Mail dropping into 'black holes' due to multiple path forwarding causing Ping Pong message failures and lost of mail delivery.

3) Ensure Personal Messages get delivered successfully to it's destination.

Click to view the AX25 UK BBS_LISTINGS
(Please provide
Paul with updated information on your BBS Status and forwarding partners)

UK AX25 BBS Forwarding Map
(2005) note a lot of these BBS's no longer exist in 2013.

For interest, Bryan G0SYR has created a roughly geographic UK Map of the BBS's showing their forwarding partners. (You will note that most of the BBS's have now closed down since this map was last generated (2005).
Only the last 3 letters of the BBS callsign are shown for clarity they are all prefixed with GB7.

should refer to the AX25 UK BBS_LISTINGS to see what is forwarded and to get an idea of international links that the BBS's provide.
The fact that a BBS is shown without links. Does not mean the BBS is not linked, simply that Paul has not been supplied with updated information.

Click to download the above in Adobe PDF Format