Wireless on Trains

How do they do it? It works in tunnels, too...

)

BigM@C wrote:
> How do they do it? It works in tunnels, too...

Sat for most of the connection, 3G/GPRS for when the sat can't be seen.
Aerials at both ends of the train mean short tunnels don't matter.

"Wireless Reader" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> BigM@C wrote:
>> How do they do it? It works in tunnels, too...
>
> Sat for most of the connection, 3G/GPRS for when the sat can't be seen.
> Aerials at both ends of the train mean short tunnels don't matter.
It doesnt work in the tunnels on the East Coast Mainline out of London - or
didint when I last used it. The connection dropped in every tunnel.

In message <(E-Mail Removed)>, Wireless Reader
<(E-Mail Removed)> scribes
>BigM@C wrote:
>> How do they do it? It works in tunnels, too...
>
>Sat for most of the connection, 3G/GPRS for when the sat can't be seen.
>Aerials at both ends of the train mean short tunnels don't matter.

The way it was being planned on our trains was with the following signal
priority:-

WiFi signal - this would be picked up in stations and depots.
Satellite - incoming traffic only
3G/GPRS - for sending traffic and when no WiFi or Satellite for incoming
traffic.

The reason for WiFi at the top of the list is to stop the train dialling
out when sat for a few hours under a station canopy (i.e. overnight) or
in a depot.
--
Snowy

In message <(E-Mail Removed)>, Roger
<(E-Mail Removed)> scribes
>
>"Wireless Reader" <(E-Mail Removed)> wrote in message
>news:(E-Mail Removed)...
>> BigM@C wrote:
>>> How do they do it? It works in tunnels, too...
>>
>> Sat for most of the connection, 3G/GPRS for when the sat can't be seen.
>> Aerials at both ends of the train mean short tunnels don't matter.
>It doesnt work in the tunnels on the East Coast Mainline out of London - or
>didint when I last used it. The connection dropped in every tunnel.
>
>
GNER should have used Orange then, there is an aerial right on the
tunnel mouth of the first one out of Kings Cross. Maintains a signal
all the way through (cries of shame!).
--
Snowy

Ian Snowdon <(E-Mail Removed)> wrote:

>The way it was being planned on our trains was with the following signal
>priority:-
>
>WiFi signal - this would be picked up in stations and depots.
>Satellite - incoming traffic only
>3G/GPRS - for sending traffic and when no WiFi or Satellite for incoming
>traffic.

Doesn't this mean the web proxy or whatever gets switched along the
route? Changing the IP is sure to break any downloads.

Ian Snowdon <(E-Mail Removed)> wrote:
>The way it was being planned on our trains was with the following signal
>priority:-
>WiFi signal - this would be picked up in stations and depots.
>Satellite - incoming traffic only
>3G/GPRS - for sending traffic and when no WiFi or Satellite for incoming
>traffic.

Peter <(E-Mail Removed)> wrote:
> Doesn't this mean the web proxy or whatever gets switched along the
> route? Changing the IP is sure to break any downloads.

Provided the IP addresses seen by the client (you) and the remote server
don't change, it's quite acceptable for the routing in the middle to
vary. That's part of what makes the Internet so resilient.

WEBSERVER -|- EXT ROUTER -- varying routes -|- INT ROUTER -- CLIENT

The internal router and your client would be on the train. The external
router would be at the network border of the railway wifi service.

Chris

BigM@C wrote:
> How do they do it? It works in tunnels, too...
>
> )
>
>
http://www.gner.co.uk/GNER/Wi-Fi/How+does+it+work.htm

Thanks to everyone who responded - this link explains it perfectly, as it
was the GNER system I was using...

)

"NBT" <(E-Mail Removed)> wrote in message
news:d6i4a9$8ci$(E-Mail Removed)...
> BigM@C wrote:
>> How do they do it? It works in tunnels, too...
>>
>> )
> http://www.gner.co.uk/GNER/Wi-Fi/How+does+it+work.htm