[SOLVED] Maximizing throughput from one physical pipe

mercury80

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Casual question....

I have two switches (not 10GbE capable) connected with one UTP, through a 16 mm tube (in the wall)... probably about 15 m long. (I have equipment to terminate TP my self.)
The switches have only two SFP uplink ports, but a large amount of copper ports for LAG (link aggregation).
I don't have equipment to terminate fiber my self, so that will probably never happen.

Can I increase the existing 1GbE throughput without going overboard?
Has anyone tried to pull fiber patch (pre terminated fiber cables) through 16 mm? Can it be done? Can I do more than one pair?
Does there exist ≥CAT5 with more than 8p that can fit through 16 mm? Like a 24p Cat5 would be pretty awesome...
 
Solution
It depends which sfp the switch supports.

Simple would be if it supports copper 10g. Some switches do and others do not. If the cable is rather short you might even get your current cat5e to run 10g. It is not officially supported but like normal cat6 cable it does work for short distances. You could run cat6a and get 10g officially.

Depends on how tight the bends are in the path but you could likely get a duplex sc sc cable run by splitting the connector so they are not side by side when you run them. If your switch supports the really expensive SFP that can do wave division then you only need a signal strand of fiber and it can run 10g using 2 different color lasers on the same fiber.

Now if what you are asking is, my...
These days the ends on preterminated fibre are almost the same size as the ends on ethernet so if a terminated ethernet cable can fit, you might be able to get a fibre to fit.

Now the real question is if you even need to do this. What are you using that is exceeding 1Gbps? There may be other solutions that will be cheaper/easier.
 

mercury80

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No... The UTP cable wasn't pre terminated... A RJ45 won't fit.
If any fiber was an option, it will have to be LC/LC...

I'm fantasizing that I can put the two connectors in short succession with some tape around and pull that through. (If that was to work I would probably get several LC/LC cables through the same pipe.)

Real answers:
  • Now the real question is if you even need to do this.
    • No
  • What are you using that is exceeding 1Gbps?
    • Don't think there are any...
  • There may be other solutions that will be cheaper/easier.
    • Leaving the CAT5e alone probably
This is strictly a "because I can" project... (and I did mention I was looking for a solution "without going overboard"...)
 
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It depends which sfp the switch supports.

Simple would be if it supports copper 10g. Some switches do and others do not. If the cable is rather short you might even get your current cat5e to run 10g. It is not officially supported but like normal cat6 cable it does work for short distances. You could run cat6a and get 10g officially.

Depends on how tight the bends are in the path but you could likely get a duplex sc sc cable run by splitting the connector so they are not side by side when you run them. If your switch supports the really expensive SFP that can do wave division then you only need a signal strand of fiber and it can run 10g using 2 different color lasers on the same fiber.

Now if what you are asking is, my switch only support 1g sfp and I want to run 2 fibers so I can run LAG then you are wasting your time.

Port aggregation has been pretty much killed off by faster ports. What it used to work very well at was to provide high speed access to a large central server. What it does not work for is to increase the speed of a single file transfer. So if say you combine 10 ports to get 10g a single file transfer can only use 1gbit.

This is because there is no actual load balancing in the official form of LAG. It uses a mathematical formula to choose the path so it is always the same for a single session because it is based on ip address and port number. Even worse it can take 2 different sessions and put them on the same connection leaving the other one unused. It only really works when there are many 100s of small sessions and the randomness of all the session lets it load balance better.

Now there are some proprietary forms of LAG not generally supported by switches. The problem with ones that say use round robin for packet allocation is that you now get packets received out of order because for example you can transfer 10 150 byte packets in the same time as 1 1500 byte packet. This many times is interpreted by the end device as packet loss so you get a lot of request for data retranmission and depending on the timing you can get session drop or at least lots of duplicate packets being sent. These are some very high end devices that chops the data up so all packets are the same size, they actually intermix multiple packets at the bit level, and then reassemble everything at the far end.

In general the preferred solution is to use faster ports and media than trying to combine cables.
 
Solution