H/W component of modern network

[Arjun Dabol]

Hi,

I have a doubt and wondering if someone can help me understand this piece of modern networking  as I am lacking filed experience (considering everything is supported remote)

here goes the question:

starting from Fiber to a router's interface , there are multiple things that come in to picture now a days and they all have different names. if someone can give me a brief description
of below itemas , how they fall in between a fiber ------router. like how these things are inter-connected.

fiber optics
POS
SPA
SIP
DWDM
OC-3/OC-48
ethernet

LineCard

Also What all other medium of connectivity than ethernet/POS today ?

TIA

[Joseph W. Doherty]

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

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In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

Your posting is difficult to address because if we answer briefly, I suspect, you'll still have questions, and non-brief answers can be very long.

Have you tried to research your terms using Cisco's main site and/or something like Wiki?

If not, also try those, and then if you have more specific questions, post again to these forums.

In any case brief answers:

fiber optics - (small) module that transforms electrical to/from optical - e.g. GBIC, X2, SFP
POS - packet over SONET - see http://en.wikipedia.org/wiki/Packet_over_SONET/SDH
SPA - Shared Port Adapter - Cisco hardware module with interfaces - may be inserted in SIP
SIP - SPA Interface Processor - Cisco hardware module that hosts SPAs - (Device(SIP(SPA)))
DWDM - dense wavelength division multiplexing - allows concurrent bandwidth channels on same fiber
OC-3/OC-48 - Optical Carrier 3 and 48 - similar in concept to (copper) T1 and T3 - see http://en.wikipedia.org/wiki/Optical_Carrier_transmission_rates
ethernet - see http://en.wikipedia.org/wiki/EthernetLineCard - module that provides edge ports, e.g. 6500's 6748

Also What all other medium of connectivity than ethernet/POS today ?

Well you still have various serial copper mediums, E.g., T1, T3, DSL.  Also, POS, which was designed to take advantage of using optical networks designed for voice is now often bypassed by optical networks designed for data (often now also carrying VoIP).

[Arjun Dabol]

Many Thanks. I want to narrow down my Q as your reply helped a lot.

POS  interface : I understand POS is packet over sonet but when we use term "POS interface" - Are they like Ethernet interface  that connect fiber optical cable to a router ? 

SPA : its a module that hosts interfaces but what kind of interfaces it can host ? can it host Ethernet / optical interface also ?

last Q : if I have a fiber coming down from my service provider and I have a Cisco High end router at my end - what all physical component i need to have in between and on my router  for a successful physical connectivity ?

[Joseph W. Doherty · Accepted solution]

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

Liability Disclaimer

In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

Sorry for the delay, I missed your follow up questions.

POS interfaces are, I believe, normally optical, but are not Ethernet optical.  Yes, for optical, they would have fiber, often same fiber used by Ethernet optical.  (Fiber, like copper, as a transmission medium supports different usage technologies.)

SPA modules are whatever the vendor provides of which its technology might support.  I.e. it has physical bandwidth limitations, so it would be unable to support an interface or interfaces that require more bandwidth than it's capable of.  Vendors will provide interfaces that they believe there's a market for.  For actual examples, just browse Cisco's SPA modules.

For a fiber connections, all you need is the correct optical interface.  This might be provided by a separate optical transceiver.  For example, if your SP is providing fiber using Ethernet, you might need a SX, LX or ZX optical transceiver.  Or, I believe, some optical interfaces will take the fiber connection directly.

[Arjun Dabol]

Thanks a ton. also if u can plz tell .

1. What is the role of  SFPs in a router , where it fits ?

2. there are something called "DWDM controllers" OR "DWDM interface" - where do they fit in a router ?

3. Where do g709 interface fits in  ?

[Joseph W. Doherty · Accepted solution]

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

Liability Disclaimer

In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

The SFP (small form plug) is a transceiver.  It connects into device (port) sockets designed for it.  It allows different media to be used on a device port.  For example copper Ethernet or fiber Ethernet.  Logically similar plugs are GBIC and X2.

DWDM (dense wavelength division multiplexing) is a different fiber technology.  It supports multiple "channels" across a single fiber stand.  It's generally used by optical networking.  Often the connectors transceivers are SFPs, X2s, etc.  A router use one much like other fiber connections.

G.709 provides a set of standard for communicating over DWDM optical transport netoworks.

Additional questions about DWDM or G.709 are probably best posted in the Optical Networking forum.