Gigabit switching.

Discussion in 'Macintosh Computers' started by jelwell, Oct 21, 2003.

  1. jelwell macrumors member

    Joined:
    Jan 31, 2003
    #1
    So when will we see a new Airport Extreme Base station?

    I know that pidly 100 BaseT switch is slowing down my cable modem downloads. ;)

    Seriously though, my new powerbook has gigabit ethernet support but Apple doesn't sell a base station that supports it. Sure, NOW it doesn't really matter since gigabit will only help on my local LAN, but it would still be nice.

    By the way, can my powerbook read and transfer data off it's hard drive that fast?

    Apple's store says YES.

    Apparently the data transfer rate on the hard drive is only 100MB/s. so what good is the gigabit ethernet unless I'm moving the contents of RAM around?

    Woopsie, it turns out I was confusing MB (megabytes) and Mb (megabits). Let's try this again.

    All in Megabits:
    Hard Drive = 800Mb/s (100MBytes/s)
    Firewire 2.0 = 800Mb/s
    Gigabit Ethernet = 1,024Mb/s
    Airport Wired Ethernet = 100Mb/s
    Airport Extreme (Wireless) = 54Mb/s

    So, it turns out my hard drive is faster than my current network and so could use some gigabit ethernetting.

    joe.
     
  2. cpjakes macrumors 6502

    Joined:
    Aug 15, 2003
    Location:
    Buffalo, NY
    #2
    Probably not necessary...

    jelwell,

    It seems to me that gigabit switching won't give you much of an advantage. I've got a cable modem on wireless router with 100Mbit switch. Here's the skinny on most numbers:

    Cable modems generally give between 384 and 768k/sec, or .3 and .7MB/sec. Regular AirPort (802.11b) gives speeds up to 1.1MB/sec. AirPort Extreme bumps that up to 5MB/sec. Whatever the configuration, I doubt your cable modem is being slowed down by your switch.

    As far as network file transfers, your PowerBook hard drive will max out around 15 or 20MB/sec. A 100 switch is about 10MB/sec. A gigabit switch would be helpful here provided you have another gigabit machine to go to. If you're that concerned about the transfers, you can file share directly between gigabit ethernet ports on the computers.

    Gigabit switches provide high speed transfers for multiple computers at a time. Only a couple of machines running on it will not tax it very much. And generally, switches with gigabit can be expensive, try Linksys, they have a couple consumer models.

    Unless you have a need to move huge files around your LAN, I think you're alright for now.

    Hope this helps...
     
  3. jelwell thread starter macrumors member

    Joined:
    Jan 31, 2003
    #3
    The cable modem message was a joke. ;)

    But the rest of your numbers don't jive with mine.

    The powerbook hard drive should get 100MB/s which I pointed out in my post. Not 15 to 20MB/s - as you mentioned - unless there's a bus issue I don't know about.

    I'm mostly dealing with video these days. Everything gets transferred to my Powerbook, either from my PC, my tivo or my firewire drives. My tivo doesn't support gigabit and my pc doesn't currently have a gigabit card.

    I think the important thing is that Airport Extreme Base station is so much more expensive than competing products, and it's not a wired switch anyways, it only has one 10/100BaseT port. So I suppose the airport extreme base station isn't really even handling my local network (excepting of course the wireless). And yeah, gigabit switches are freaking expensive! sheesh, I can buy an 8 port 10/100BaseT router/switch firewall for less than a 4 port gigabit switch.

    I'd just like to have everything rolled into the Airport Extreme Base Station.

    Airport Extreme Base Station 2.0 wishlist:
    4 or more switched gigabit ports.
    802.11g.
    external antennae.
    print server.
    modem dial in.
    cake.
    and eat it too.

    joe.
     
  4. saabmp3 macrumors 6502a

    Joined:
    Jul 22, 2002
    Location:
    Tacoma, WA
    #4
    Re: Probably not necessary...

    umm, 100 Mb/sec networks run at 12.5 MB/sec and gigabit networks run around 110 MB/sec (there is alot of overhead, I forget why and it might be fixed by now). Servers which are handing out lots of connections might need gigabit, everything else is just sorta meh. My PB has a gigabit port too. I hooked it to a Cisco gigabit switch just for the hell of it once and it realyl didn't impress me too much. Oh well.

    BEN
     
  5. Catfish_Man macrumors 68030

    Catfish_Man

    Joined:
    Sep 13, 2001
    Location:
    Portland, OR
    #5
    If the PB's HD got 100MB/sec you'd be seeing high-end PC towers being loaded up with them. The HD's connector (ATA100) supports 100MB/sec, but 15-20 sustained sounds reasonable for the drive (the very best desktop drives max out at 60-70MB/sec peak and a good deal less sustained iirc).
     
  6. Fukui macrumors 68000

    Fukui

    Joined:
    Jul 19, 2002
    #6
    Yea, 100MB/Sec is the max speed of the ATA 100 Bus, the actual disk isn't actually going to give you more than 20 or 30 MB/sec tops, and thats for totaly congruent data such as a huge .VOB or .DV file. 100 MB/Sec Bus is much more useful if you happen to have a raid setup, then you can get closer to the theoretical max speed of the bus.
     
  7. acj macrumors 6502

    Joined:
    Feb 3, 2003
    #7
    I have a gigabit network. I transfer lots of large files, and usually get about 20-30% network utilization, which would be 200-300% on a 100 base network, so I do get a good speed increase. That translates to 25-37 megabytes per second. This is from RAID arrays spinning at 7200RPM, not piddly laptop drives at 4200 or 5200 RPM.
     
  8. tomf87 macrumors 65816

    tomf87

    Joined:
    Sep 10, 2003
    #8
    It's impossible to get 200-300% utilization, becuase utilization tops at 100% on everything. Are you referring to 10 times the speed of 10BaseT? I've never seen anyone get exactly 10 times the performance when moved from 10BaseT to 100BaseT. But also, it depends on whether you are connected to a switch or hub. Hubs only support half duplex, which means that only one device can "talk" at one time. Switches support full duplex with means that multiple devices can talk simultaneously. With just two devices just transferring files, you are going to be lucky if you hit gigabit speeds. Even still, you won't get the throughput on the busses of the laptop either. You'd need to use the new PCI-X busses to get those speeds up.

    The speeds that everyone refers to are theoretical, not practical. Even the new Serial ATA drives don't hit the maximum 150MB/sec rate the bus supports.

    What kind of RAID arrays do you have, acj? RAID 5, 0+1, 1+0? Kick those puppies up to 15k Ultra320 running RAID 0+1 and connect them across a 2Gb Fibre Channel Loop and now you're talking some speed and redundancy.
     
  9. Lanbrown macrumors 6502a

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    Mar 20, 2003
    #9
    That is not entirely true. The backplane speed of the switch dictates how many can talk at the same time. If the backplane has a speed of 200Mbps, it can only switch that amount. If you have one that has a 4Gbps backplane, more devices can talk simultaneously. Several years ago, most consumers switches had a 200Mbps backplane speed.
     
  10. tomf87 macrumors 65816

    tomf87

    Joined:
    Sep 10, 2003
    #10
    Yes it is always true, a switch will always support two or more devices talking at the same time; the backplane and memory in the switch determine how many can talk (like an interstate: it will always support two cars at the same time, but the number of lanes determines how many can fit at one time).
     
  11. acj macrumors 6502

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    Feb 3, 2003
    #11
    I said I get 20-30% utilization on the gigabit network. in 100BaseT speeds, that's 200-300%. 15k drives would be great, but I prefer to have a terabyte of raid5 space for under two grand.
     
  12. tomf87 macrumors 65816

    tomf87

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    Sep 10, 2003
    #12
    Ah, I see.. I misunderstood what you were saying. Yeah, the SAN solution is a bit expensive. We just bought a SAN solution and it cost us $40,000, and that's without the disks.. Ouch!
     
  13. benixau macrumors 65816

    benixau

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    Oct 9, 2002
    Location:
    Sydney, Australia
    #13
    Ok - i sent a 100MB file to my bro on his iMac - has good HDD speed and 100BaseT. Took about 60secs.
    Sent the same file to my dads PowerMac which has 1000BaseT. Took about 18 secs.

    We only have a 10/100 BaseT switching router. So even over a 100 network the Gigabit -> Gigabit is faster - significantly.

    Gigabit is good. 100 is good. 10 is ok. 1 is a lame way for pc manufacturers to ahve three numbers in their network card specs. (Apple says 10/100/1000, they say 1/10/100 <- cheap huh)
     
  14. tomf87 macrumors 65816

    tomf87

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    Sep 10, 2003
    #14
    It doesn't work that way. Even if you have a gigabit NIC, connecting it to a 100BaseT port will only yield a possible 100 Mb connection.

    With that said, many other factors come into play, such as how much RAM does each system have, what processes are running, and how much swap is being used.

    Now, comparing an iMac to a Power Mac could cause skewed results. Some of the iMac's only have ATA33, and some have ATA66. I believe the Power Mac has had ATA100 for some time now, and that could cause it too.

    As for the 1/10/100, I have never seen a figure like this as ethernet doesn't have a 1 Mb standard. Even back in Thinnet and Thicknet days, 1 Mb didn't exist.
     
  15. benixau macrumors 65816

    benixau

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    Oct 9, 2002
    Location:
    Sydney, Australia
    #15
    i told you - it was a cheap way for pc manufacturers to have three terms in the network spec.

    Also, i am saying that even in a 100 network, the Gigabit NIC can ignore the overhead.

    Also, we have a higher end netgear router with an 800Mbps backplane: it has 8 ports.

    The thing is that i saw these speeds: i know HDDs can have an effect but this ....

    iMac: 768MB
    Pmacs: 768MB

    Look i know machine differences have an effect but still - this is too large not to attribute some of it to the better NIC.
     
  16. tomf87 macrumors 65816

    tomf87

    Joined:
    Sep 10, 2003
    #16
    It is a better NIC, but I still doubt that the faster NIC helped. It is quite possible that the network processors are different, and I've found that some of my 10/100 servers like to be nailed at 100 Full and perform optimally, while my newer servers with 10/100/1000 like Autonegotiate better. The new servers with 100 Full nailed only were getting 1 - 2 MB / sec. Since the NIC's in Mac's are auto by default, this could cause it too.

    I'm still curious as to where you saw the 1/10/100 thing.. I'd be interested in seeing something that amusing. :)

    I don't think an 800 Mb backplane for 8 x 100 Mb ports is considered high-end. That's just 100 Mb per port, which is standard in today's terms. I don't think anything NetGear related is high-end.
     
  17. benixau macrumors 65816

    benixau

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    Oct 9, 2002
    Location:
    Sydney, Australia
    #17
    if it was modern gear i would agree. It isnt new (few years old). It is "reliable" though. If i could afford something i would get it.

    My school on the otherhand ..... cisco switches (gov't paid for it).
     
  18. yamabushi macrumors 65816

    yamabushi

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    Oct 6, 2003
    #18
    It would make sense for Apple to include gigabit in Airport base stations, if only to stay consistent with the cards in newer Macs.
     
  19. Lanbrown macrumors 6502a

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    Mar 20, 2003
    #19
    You used a blanket statement which is just not true all of the time with consumer class switches. You said two or more, if you have two devices running full speed, that could saturate the backplane and thus it is now a blocking switch. If the number of ports times by the maximum ports speed is higher then the backplane speed, it is a blocking switch.

    Netgear was the consumer division of Nortel Networks. So they don't make anything high-end as that was a different division.
     
  20. tomf87 macrumors 65816

    tomf87

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    Sep 10, 2003
    #20
    Well, that would increase costs to include gig ports too, and since you've only got one LAN port on the base station, it makes it fairly useless.
     
  21. tomf87 macrumors 65816

    tomf87

    Joined:
    Sep 10, 2003
    #21
    I see what you're saying. NetGear was part of Bay Networks some time ago.. Did Nortel buy Bay or did Bay just sell the NetGear line? I never kept up with either of those companies.
     
  22. Lanbrown macrumors 6502a

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    Mar 20, 2003
    #22
    Nortel bought Bay Networks. Bay created Netgear as their consumer line, one reason why their products were in the metal cases that are typically found in enterprise equipment. Then Netgear was spun off and is on its own so Nortel could focus on their core business. I never figured out why Nortel bought Bay, I had to work with a group that used Nortel equipment, like their voice switches that phone carriers use. The same basic switch was used for home phone service as well as mobile phone use like analog and CDMA. They (Nortel) apparently knew nothing of LAN networks as their first product (EIU) to connect to the switch to a LAN for management, billing data, etc; before that, only x.25 was used. That EIU needed RIP v1 to run and work properly, as well as needing a front-end IP as well as two IP's on the backend and the backend was a full class C. It took them two software releases to get rid of the RIP requirement, which was equal to about three to four years. Their techs hated that we used the same class C network for all backend EIU networks and said that it wouldn't work, different IP's were used though. Their upgraded version called the SDM had its own problem. It wouldn't work in HSRP environments and still could not handle more then 10Mbps throughput. The other problem that it had, it gave two options for what Ethernet standard you wanted to use. One would allow people on the same network segment to access it but not someone on a different segment. The other option would allow people on other segments to access it, but not people on the local segment. All of this was after Nortel bought Bay. I feel sorry for the people that use networking gear from Nortel as they just don't seem to have much sharing of resources and they just didn't seem focused on the networking market or even understand it; one reason why they probably spun Netgear off, which IMO was a bad move. Cisco just renewed their efforts into the consumer line by purchasing Linksys. Cisco had several failed attempts into the consumer line with their low-end gear, all because of their prices.

    Even with Netgear being an independent company, they will probably never enter the enterprise or midsize business market. I can see the consumer, SOHO and maybe the small business and that it is. While the markup is great for the top end gear, it is a very tough market and ever changing market conditions. A lot of R&D is required as well. You either have to innovate or but companies that do.
     

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