Indeed. Arista does (did?) make at least one platform where you can do this.
-----Original Message----- From: NANOG [mailto:nanog-boun...@nanog.org] On Behalf Of Marian Durkovic Sent: Monday, February 5, 2018 2:33 PM To: Baldur Norddahl <baldur.nordd...@gmail.com> Cc: nanog@nanog.org Subject: Re: 40G reforming Many switches based on BCM Trident ASIC allow you to configure 4 consecutive SFP+ ports as 40G link (not LACP, but using real hardware 40G framing). In such case, you can plug 4 DWDM SFP+ modules directly into the switch, without the need for any reformer. M. On Mon, 5 Feb 2018 20:03:33 +0100, Baldur Norddahl wrote > I may need to clarify that I do not want to break the port into 4x10G > as such. To the switch this will be an ordinary 40G link to another > switch far away. > > I want to take advantage of the fact that 40G is transported as four > individual streams. Each of the four streams are to be converted from > 850 nm to a 1550 DWDM channel (one channel per stream). And the > reverse at the other end of the link. > > The point of doing this is that 40G DWDM modules are not generally > available and neither are 80 km modules. > > I need a true 40G channel so 4x10G LACP is not an option here. For the > same reason I am unable to accept a solution that splits the 40G port > into 4x10G and then perhaps recombines using LACP. Instead I am > looking at an optical solution that is invisible to the switch hardware. > > The only doubt I have about the proposed solution is whether the frame > format of the 10G substreams is somehow incompatible with what goes on > in the reformer. As I understand these reformers they are little more > than two SFP(+) modules connected back to back. And therefore it > should not matter that the frame format may be different. > > Regards > > Baldur > > Den 5. feb. 2018 7.20 PM skrev "Paul Zugnoni" <p...@wish.com>: > > Whether a 40G port can be broken into 4x10G is dependent on the > router/switch hardware and the optic you use. Good news is that most > 40G ports are capable of being broken out into 4x10G, since a 40G port > is usually operating as 4x10G internally anyway to the ASIC. The QSFP > you'll need would be a 40G-SR4 for MTP/Multimode or 40G-LR4 for > MTP/Singlemode (or a lower power, less expensive equivalent). This is > a pretty common use of 40G ports. All 4 10G ports would then be at > 850nm or 1310nm, which you can then plug into any 10G SR or LR ports. > > What router or switch platform is driving the 40G? > > Paul Z > > On Mon, Feb 5, 2018 at 7:57 AM, Baldur Norddahl > <baldur.nordd...@gmail.com> > wrote: > > > Hello > > > > Is it possible to reform a 40G signal as individual 10G links? > > > > The idea is to use a 40G QSFP multimode MTP module such as > > https://urldefense.proofpoint.com/v2/url?u=https-3A__www.fs.com_prod > > ucts_44058.html&d=DwIDaQ&c=Hlvprqonr5LuCN9TN65xNw&r=Iw8ah1pcqZhOErIj > > aFRfuA&m=wWoshgttJT0E6q6-qJzP_ZcIrEz_EP88taPCbvAiK2Y&s=_rJfOmyDlGmPG > > C6M5FbhQ1V8_mho1OCpkcuYRNlaOvA&e=. Then connect it using a MTP > > breakout cable such as > > https://urldefense.proofpoint.com/v2/url?u=https-3A__www.fs.com_prod > > ucts_68049.html&d=DwIDaQ&c=Hlvprqonr5LuCN9TN65xNw&r=Iw8ah1pcqZhOErIjaFRfuA&m=wWoshgttJT0E6q6-qJzP_ZcIrEz_EP88taPCbvAiK2Y&s=Cz0mCyM3dtcHoZ7lGy7uyroI_Y7AwmKXdnYNFIF0rPI&e= > > to get four dual fiber connectors. These are then connected to four 10G > > SFP+ multimode modules such as > > https://urldefense.proofpoint.com/v2/url?u=https-3A__www.fs.com_products_11589.html&d=DwIDaQ&c=Hlvprqonr5LuCN9TN65xNw&r=Iw8ah1pcqZhOErIjaFRfuA&m=wWoshgttJT0E6q6-qJzP_ZcIrEz_EP88taPCbvAiK2Y&s=l-9OAiUxeydRJCJc7d1kTKPVSkwQlkV4xkZFlbFxyRs&e=. > > The reformer could be > > https://urldefense.proofpoint.com/v2/url?u=https-3A__www.fs.com_products_43721.html&d=DwIDaQ&c=Hlvprqonr5LuCN9TN65xNw&r=Iw8ah1pcqZhOErIjaFRfuA&m=wWoshgttJT0E6q6-qJzP_ZcIrEz_EP88taPCbvAiK2Y&s=NwCHiC_boNNs7zCOgJFRZ5nmZOVEPBovGYNTtdQ_pCE&e=. > > And finally the reformed signal can be transported using anything > > including DWDM modules such as > > https://urldefense.proofpoint.com/v2/url?u=https-3A__www.fs.com_products_44058.html&d=DwIDaQ&c=Hlvprqonr5LuCN9TN65xNw&r=Iw8ah1pcqZhOErIjaFRfuA&m=wWoshgttJT0E6q6-qJzP_ZcIrEz_EP88taPCbvAiK2Y&s=_rJfOmyDlGmPGC6M5FbhQ1V8_mho1OCpkcuYRNlaOvA&e=. > > > > Just using fs.com as a reference to the kind of equipment I am > > talking about. Many other vendors offer simelar products. > > > > The motivation for doing this is to get access to the many options > > that are available for 10G optics but not possible with 40G. > > > > Regards, > > > > Baldur > > > >
