Web Hosting Talk : Web Hosting Main Forums : Colocation and Data Centers : My ISP Datacenter: 155Mbps, fast?

[TeachMe]

1. My local ISP datacenters has 155 Mbps backbone. Is 155 Mbps consider a good speed in the industry? 155 Mbps = 19.4 MB/second. Is this calculation correct?

2. We connect our server to the datacenter with a 10/100 base card. So does that means we can go as high as 100 Mbps instead of 155 Mbps?

[TeachMe]

3. If 19.4MB/s is correct, does that means if there are 10 customers using that backbone, each of them get only 1.94MB/second ?!?!

[webworkz]

If the colo DC had 10 customers buying 1.94MBps from them [basically 10 T1 lines, or 1/3 of a full DS3, per customer], they would hopefully have the money to increase their bandwidth from the carrier side, or have additional fibre installed.

I'm assuming they have multiple DS3's, or an OC3 + DS3.


As for your second question, yes; your maximum throughput would be 100Mbps ... which you won't get close to, at all.

Think about it: a 10Mbps net connection, at maximum throughput, pushes ~3200/GB per month.

So, your ISP's total capability is 49,600/GB of transfer per month.

Do you really expect to use that much?

[tilted]

First, 155 Mbps is an OC3 if they said "backbone" in the singular form of the word. If they pluralized it, it would most likely be 3 DS3s (45/Mbps each).

Second, converting between Mbps and MBps doesn't do you much good unless you're estimating transfer times on large files.

Third, T1/DS1, DS3, FE, OC3, OC6, GE, OC12 are measurements of capacity, not of "speed".

Think of it as XXX lanes on a highway, where all vehicles go at the speed of light... The question will be, how many vehicles can you cram down that highway before it starts choking.

A data center with an OC3 will serve your needs fine as long as they aren't peaking out on it. What I'd be more concerned about is the redundancy in their lines and capacity increase planning.

Also, a 100 Mbps port will serve you just fine, and if you're starting out, a 10 Mbps port will likely be fine too. Your only likely options from there are either bonded FastEtherChannel (FEC) or GigabitEthernet (GE).

George

[webworkz]

Originally posted by tilted
First, 155 Mbps is an OC3 if they said "backbone" in the singular form of the word. If they pluralized it, it would most likely be 3 DS3s (45/Mbps each).

Second, converting between Mbps and MBps doesn't do you much good unless you're estimating transfer times on large files.

Third, T1/DS1, DS3, FE, OC3, OC6, GE, OC12 are measurements of capacity, not of "speed".

Think of it as XXX lanes on a highway, where all vehicles go at the speed of light... The question will be, how many vehicles can you cram down that highway before it starts choking.

A data center with an OC3 will serve your needs fine as long as they aren't peaking out on it. What I'd be more concerned about is the redundancy in their lines and capacity increase planning.

Also, a 100 Mbps port will serve you just fine, and if you're starting out, a 10 Mbps port will likely be fine too. Your only likely options from there are either bonded FastEtherChannel (FEC) or GigabitEthernet (GE).

George

Is this in reference to my post or the thread-starters?

[TeachMe]

Webworkz, I love your explanation about the 49,600GB/month! That makes everything clear.

tilted, I understand now, it is the LOAD (capacity) instead of speed. That's what I am confused before this. I used to think, "How long would it takes for a 155mbps line to download 3 redhat linux ISOs.".

[Kx-2]

That's a subjective question. You have to ask the datacenter how many customers they have and what are the bandwidth utilization levels for the 155Mbps pipe (assuming it's not multi-homed).

[TeachMe]

Do 'multi-homed' means they have a few 155Mbps pipe?

[tilted]

Originally posted by TeachMe
tilted, I understand now, it is the LOAD (capacity) instead of speed. That's what I am confused before this. I used to think, "How long would it takes for a 155mbps line to download 3 redhat linux ISOs.".

It would take as long as it takes for a) their disks to make the data available to the server, b) their server to make the data available to their local network, c) their local network to make the data available to the Internet, d) the Internet to make the data available to your local network, e) your local network to make the data available to your server, f) your server to make the data avilable to your disks, and g) your disks to be able to write said data.

That said, gauging connections and speed based on file transfers involves variables, some of which change significantly based on time-of-day. How many pages of text does a 5.25" floppy hold? 10 MB hard drive? 60 MB hard drive? 144 GB hard drive?

Ask them about a) redundancy of their connections, b) redundancy in their network gear, c) peak usage statistics, d) upstream commitment levels and burstability, and e) a tour if they're conveniently local to you.

Better yet, ask them to educate you. If they're confident in the service they're selling to you, they should at least be able to explain some basics to you as well.

Best of luck,

George

[sgreene]

MBps != Mbps

MB = megabyte. In laymans terms, 1MB = 10mb

1.9MBps is roughly 20mbps.

I'd clarify with the data center as to how they are on their capacity. I'd assume if they are at the OC3 level, they do atleast 45mbps.

[KDAWebServices]

1MB != 10Mbit

1MB = 8Mbit, if you're going to give someone a rough calculation, then at least give them the right one as well, it's not that difficult to multiply or divide by 8 anyway.

[apollo]

hmmmm not bad, I hope they have some backup line with a different provider or perhaps "multihoming".

ps. people are "pampered" nowadays.... some countries still connect using very slow satellite uplinks... and they are not bi**ing at all

[sgreene]

I was using laymans terms to simplify. In this case dividing by 10 or 100 is just easier

[snickn]

But saying that 1mbyte=10mbit is plain wrong. nothing more to it, it's not rough laymans terms, it's just wrong.

saying 1mbyte = 8mbit is a good rough estimate, I realize that some folks here may not have quite reached the grade where they learn to multiple and divide by 8, but for those who can, let's not give wrong information.

8 bits to a byte. simple. not 10 bits to a byte. that's wrong.

anyhow. it all depends on how much they push through that OC3, and who it is too, if it's cogent, and they have it at 97% usage, than no it's not good. if it's level3 and they have it at 3% usage, then yea that's great.