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12

Have you looked at using a separate external mux? I've run parts of our rings on pairings of ordinary (but colored) 10G optics and passive CWDM muxes with a single strand on each side. This let us also do multiple parallel links at the same time (we used 8 channel muxes).


11

Will the computers be able to connect to the NAS at 10GbE? Yes, if both the computers and the NAS are connected to the switch at 10GbE and do not require routing (ie. both are in the same subnet and VLAN). Will the router slow things (other than internet) down? It will slow anything which passes through it down to gigabit, but only if is faster to begin ...


11

You'll find discussion of this elsewhere - see 'Why would I choose Copper over SFP+ for 10GbE?' - but broadly speaking SFP+ DA is, ignoring distance: Cheaper at the adapter side. Lower power and latency. Gives added flexibility if you need to move to fibre later. 10GBase-T on the other hand is: Cheaper at the connector side - patch leads being cheaper ...


10

Short answer: in theory yes, in practice no. Long answer: There are SFP+ optics which can also work at 1 GbE, I've talked (sorry, no other source than that) to people who were experimenting with it and were able to get it running. Unfortunately it is highly dependable on the device you plug the optics in, i.e. not every device in the test was able to tell ...


10

Wavelength and rate are the two big ones. As you're dealing with 10G ethernet, rate isn't in question. (if we were talking about fibre channel, or SONET, then it would matter.) For your specific case, they are providing service through a 1310nm "LR" (long-reach) interface. The "SR" (short-reach) optics will not work -- wrong wavelength (850nm) and wrong ...


10

Just to address the SNMP portion of your question, I'm guessing that you are seeing the 4.3Gbps result from querying the SNMP object 'ifSpeed'. If so, you are simply getting back the maximum value that is possible from a 32-bit object (i.e. 2^32-1). This is the expected behaviour for a 10Gbps interface. You will need to query 'ifHighSpeed' for the interface ...


8

You are correct. SR4 works because it's four fibres. LR4 doesn't because it's four lambdas. Even if you break out each one -- good luck finding 10G-LR optics at the exact wavelengths LR4 requires, the module itself doesn't support operating at 4x10G -- the data rate on most is 40G only.


7

You're talking about 10GBASE-T - most other 10G flavors use straight 64b/66b. Two consecutive PAM-16 levels (on each lane) represent one two-dimensional symbol. Not all possible 256 symbols are used, but they are selected from 128 maximally spaced combinations (DSQ128). Of these 7 "raw" information bits, 3 are uncoded data, 4 are used for low-density parity ...


7

From IEEE 802.3 Clause 50.1: (emphasis mine) The WAN Interface Sublayer (WIS) is an optional PHY sublayer that may be used to create a 10GBASE-W PHY that is data-rate and format compatible with the SONET STS-192c transmission format defined by ANSI, as well as the Synchronous Digital Hierarchy (SDH) VC-4-64c container specified by ITU. The purpose of the ...


7

If you have a switch with a default configuration, spanning tree will block ports when they come up until the forwarding timer expires. You can configure portfast on ports that have end hosts on them to allow spanning-tree to put the ports immediately into forwarding mode.


6

A passive wavelength-division multiplexer, such as a CWDM or DWDM mux, would probably be your best bet; this is how Service providers supply fiber especially longer distances from their local Hub site. It is probably a larger investment upfront but it would also allow you to get more out of your existing leased fibers. This is also assuming that your lease ...


5

You were closer than you think to getting it working. In fact the problem may have simply been that flow control wasn't enabled on the switch. The ethtool source code (rev 3.18) and a register interface for a part I'm familiar with, reveal an explanation for the behavior you observed. The 802.3x standard defines flow-control, but I haven't looked there in a ...


5

Most of this doesn't matter, ethernet flow control has never been widely supported and most switch devices will respect PAUSE frames, but not send them. That being said, your questions can be addressed fairly easily: Not exactly. You can still send pause frames, but your card won't respect ones sent by the switch (which you will likely never get anyhow). ...


5

Little late to the website so you may have moved on but, We use Solarwinds. Under the edit node properties there is a check box for 64-bit counters. It is probably not checked. Seen the problem you've described for some non-Cisco products in Solarwinds. Also from the manual for some manufacturers. If the added node supports 64-bit counters and you want to ...


4

SFP+ modules leave more circuitry to be implemented on the host board whereas XFP or XENPACK implemented those circuitries inside the module. Normally, you don't have to know that because you just plug the correct device in the corresponding hole SFP+ are a little smaller, and the module can be backward compatible with 1G SFP (if device allow it, which ...


3

You would definately see a benefit. You are sharing the 1Gbit link to your server with several clients so your bottleneck would be a the 1Gbit link to your server. Once you have 10Gbit connected, that pipe to your server has increased and you can server those clients much better concurrently. So imagine two clients downloading files from the shared server ...


3

It depends on your bandwidth utilization. If your current 1G connections to the server are not fully utilized, then you won't get any benefit from 10G. Although there's nothing bad in 10G, it may be useful in the future. If your current connections are fully loaded, then you will rid of oversubscription by using 10G, which will improve user experience.


3

I'm not sure about the IEEE standard, but Avaya switches only support autonegotiation for 10/100/1000 Mpbs. Autonegotiation isn't supported for 10 Gig connections. This guy breaks it down a little bit. http://networkn3rd.wordpress.com/2013/04/15/10g-auto-negotiation/


3

Problem solved: Somewhere along the troubleshooting path the SFP was removed and reinserted without rebooting the router. We tried a reboot today and the interface came up successfully. I don't know if this is a documented behavior or not, but it makes sense - try a reboot if all else fails.


3

10G BX SFPs do exist! I don't know if you can get Cisco branded ones (if you're using cisco switches) but I have found generic ones before. Just google for "SFP-10G-BXU-10km" (or SFP-10G-BXD-10km) and you should find several suppliers. The supplier I got a quote from makes them "cisco compatible" and "hp compatible" so you should have no problem having ...


3

As long as all workstations are on the same VLAN as the NAS, you won't need a 10Gig router.


3

You simply cannot mix shielded and unshielded parts in a link. The shield only works if it continuous end-to-end and properly grounded on both ends. The actual wires in shielded cabling cannot meet specifications without working shielding. Having unshielded connectors means that the shielding is broken on the link, and it is not properly grounded. ...


2

Just for people looking at this answer now (close to 3 years after the original answers): today you can get QSFP+ PLR4 transceivers that support 4x10G breakout over SMF (long range). These transceivers work by using 4 transmitters on the same wavelength but on different fibers.


2

This transceiver can do both 40G-LR4 and 4x40G LR.


2

We cannot know for sure what Juniper refers to when stating "system capacity 80gps" If we take the embedded 4 x 10G interface and we use them at full duplex then we get 80gbps. So it could refer to this fact. In this case adding line card would increase this number. MPPS is much more informative as it refers to the actual capacity of the switch of ...


2

I know that with the WS-C4507R+E supervisor, you can use the WS-X4712-SFP+E Catalyst 4500 E-Series 12-Port 10GbE (SFP+) line card. The SFP+ slots can use either 1 Gb SFP or 10 Gb SFP+ transceivers. There is a caveat: the ASICs on the line card each control three ports, and the ASICs can only handle 12 Gb each. This gives you four ASICs per the 12 ports on ...


2

The difference here is incredibly trivial - literally on the order of single-digit nanoseconds. The amount of time it takes to get the packet organized and across the switch is likely 2- to 3- orders of magnitude higher (and you're still in microseconds at that point) - and that's before you consider how long a host takes to actually receive, decode and ...


2

The OM3 fiber you linked to should do nicely, OM3 supports 10GBASE-SR for up to 300 m. As per Ron's comment, you should make sure that the fiber is crossed over - the (left) transmitter side needs to connect to the (right) receiver side and vice versa. There is no Auto MDI-X for fiber. Generally, you need to check for device compatibility before buying a ...


2

First a 10 Gbps network adapters use SFP+, not SFP. Next, you can get a 10GBase-T SFP+ module for your adapter, rather than one of the fiber variants. In most cases, 10 Gbps adapters will have SPF+ slots so that you can choose which type of cabling you are using and get the correct SFP+ module. You also need to understand Category-8 cabling, which is ...


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