Based on your inputs, you have a OC3 in your office this OC3 connects your where.
You cannot use this OC3 at your home, i think you have got it.
To answer your question on how data reaches form one point to another point
lets go through this example below.
Point 1 <---> Last Mile <--->Telco Cloud <---> Last Mile <--> Point 2
a) Point 1 uses a last mile as normal analog telephone line, in which case to conenct to
Point 2 it has to dial the Point 2 telephone number. Both points are using Modems to
modulate and demodulate the signals sent on the wire they do the actual analog electrical
signal to digital ones and zeroes conversion.
Now when point one dials the number to of your point two, it first goes by default to your
local exchange, there the incoming dialed number is checked, if the prefix is local it checks
for further local digits which tells it the number is connected to which exchange switch.
So as per the dial plan the incoming call is forwarded to the respective exchange switch.
That switch which connects to point2 forwards the call to point2 and lets the two points
negotiate the call parameters upon call setup. And then the modems upon handshaking
form an end to end session and start transmitting data by converting and reconverting from
digital to analog electrical signals.The repetiion of amlification of the received electrical
signals is done by your exchnage switches.
b) you use a deicated connection, in this case there is no routing based on numbers its pure P2P
connection between two points via your telco's digital exchange switches and they do the
cross connects between two points.
c) Why other telco's are involved. Assume your Point1 is located on telco1 and point 2 is on telco2.
How do you connect both. For such cases there are exchange point generally called MMR or
Meet Me Rooms, where carrier connect to other carriers to carry the locally hauled traffic
to be put on to other carriers.
So for Example
Point 1 <--OC3/DS3--> Last Mile <--->Telco 1 Telco 2<---> Last Mile <-STM16 Chan-> Point 2
IF your main point has secure and invested for a last mile and connectivuty for STM16 they can connect
multiple locations assumeing they are DS3/OC3 and haul them back to main locaitons via a MMR to
the main location. This is a typical scenario why you need to involve other telcos, the main reason
being one point has already invested in a last mile and second important thing one of the telco;s
doesnt have a presense to provide service in the location where your other end point is located.
Now the question is how do you connect to your office from your home.
Here a a few methods on how you can connect.
Now coming to your DSL access this will provide you internet access. So using the option
of INternet you can connect to your office and they also should have a high speed internet
connection.
Second option via DSL is you connect to a local exchange DSLAM and the provider bridges
you incoming PVC onto a specific VLAN and carries this VLAN till your office on his
Metro E cloud. For this you office should also have a DSL or ethrent conneciton to this
same service provider.
Apart from this, there isnt any specific or one single document covering all the basics
of physical media types used under networking and how they are provisioned.
Digging for each and every specific query withing books for a particular topic
would be of help to you for specific documentation you need.
HTH-Cheers,
Swaroop
