Network Management

TheSkywaves


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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QRZ callsign lookup:

Network Management


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

Reviewed 17.5.2018
New Linux nodes England
SysOP NOV Callsign Location County Active
G0HXT   Witley Surrey Sep 2015
Offline
G0WDA GB7ESC Blackpool Lancashire Mar 2015
G1GXB GB7SOU Southampton Hampshire < 1994
G0AOZ MB7NBA Bampton Oxfordshire < 1994
G3ZFR GB7COV Corley West Midlands < 1994
G4APL GB7CIP Caterham on the Hill Surrey < 1994
G4ELM   Liss Hampshire Aug 2016
G4IRX   Nottingham Nottinghamshire Jan 2017
Offline
G4MKI   Herne Bay Kent Sep 2016
G4TNU GB7IPF Amersham Buckinhamshire < 1994
G4VSS MB7NMI Warrington Cheshire Sep 2017
G6VEY   Bourne South Lincolnshire Feb 2018
G7ICD   Runcorn Cheshire 2013
G7OAH   Bicton East Cornwall Aug 2016
G7VJA GB7COW Hartland North Devon Aug 2016
G8DZH   Epping Essex Sep 2013
Offline
M0JFP GB7JFP Staines West London Jun 2013
M0NXP   Southamptom Hampshire Jan 2018
Partime
M0SKF GB7NWG Wood Green North London Mar 2018
M1DUO   Cambridge Cambridgeshire Aug 2016
Offline
M6ORT   Southgate North London Feb 2017
         
MB7NBA G0AOZ Bampton (XR IP Router) West Oxfordshire Feb 2017
Is this list complete?
73 de Paul G4APL

Network Support and history
PS. Paul has assisted and supported many of the SysOp's in the list and others not in the list above, in configuring their systems.
Several of which have thanked him for sharing his networking and linux knowledge, allowing them to advance in thier technical careers.

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 SysOps and SysOps around the London and Home Counties to ensure that the CatRad nodes (up to sixteen running TheNet X1J during the period 1988 to 2001)

These were
over three sites GB7CP <19200baud 70cm link> GB7CR (In Caterham Surrey) and <9600baud 70cm link> GB7HW (now closed 3 June 2001) near the M40 motoway Junction 5.  Enabling linking to Didcot and radio paths to Coventry newotk 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 Nework.

GB7CP provided 70cm 9600baud RF links to Crawley, Littlehampton and or to Worthing.
and a 70cm 1200baud link to Hastings.  Which had Radio lnks to Belguim.

Since
 2002, we ran all our TNCs (Terminal Node Controllers)  in Kiss mode with the JKiss eprom image installed  connected via 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. 

In our view this has worked very well for the UK for the past 24+ 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 SysOps around the UK and the rest of the world that are now experimenting with Xrouter, LinBPQ, xnet, Linux builtin network infrastructure..

NetRom path routing qualities
SysOp's that run Node's that insist on using 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 routing tables being broken, where SysOP's use very High Minimum quality values or INP3.
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 parth vaules. Then make adjustement using the 'route command' Or refusing a direct route linking request to gb7cip.

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 minimun quality 190 or 200 (needs to be confirmed) to reduce the number of entries in their node tables.

Currently in 2017/18 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 Provoder) broadband download allowance.
Also incompatable and Not a good use of the ongoing radio interfaces that are linked.
Which are CONTINOUS!! Using up unnessarry Internet Broadband bandwidth.

Now G4APL is seeing unsoliciated (uninvited) UDP links to gb7cip being established, sending their node broadcasts every 5 to 10 minutes.  (also with max path value of 255/255 from a BPQ system)
Without consulting the sysop 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 igonred, 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.

Management

No
te: adjustments are made to the obsolescent node values when using node broadcast less than every 60 minutes to be compatible with other systems.
e.g.
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

Summary
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.

Local
NetRom Network Routing gets hi-jacked due to the 255/256 and INP3 timer path vaules.

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.

TESTING THE AX25 and amprnet PERSONAL FORWARDING PATH TO AND FROM ENGLAND
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
RO
Via amprnet     ping@gb7cip.ampr.org

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

UK PACKET RADIO SSID's
as used back 1986-2003
APRS PACKET RADIO SSID's

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.

You
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