Editor’s Note: This is the second of a four-part deep dive series into High Density Experience (HDX), Cisco’s latest solution suite designed for high density environments and next-generation wireless technologies. For more on Cisco HDX, visit www.cisco.com/go/80211ac. Read part 1 here.
With any new technology comes a new set of obstacles to overcome. 802.11ac is no exception. Last week we talked about CleanAir for 802.11ac and why spectrum intelligence still matters. Another challenge is scalability. In this post I will give you some details on new HDX feature, Turbo Performance, which allows the AP 3700 overcome common scaling issues to scale amazingly well.
What’s Different with 802.11ac?
802.11ac means higher data rates, which means more packets per second (PPS). There are three reasons for more PPS with 11ac: wider channels, increased modulation and increased aggregation. Channel width doubled to 80 MHz, modulation increased from 64 QAM to 256 QAM, and aggregation increased from 64k to 1MB!
With 802.11n, an AP might have had to push 30,000 1500 byte packets per second through the APs data plane. Today with 802.11ac that could now be 75,000+ PPS. More PPS means more load on the APs CPU, so to really keep up with the demands of 802.11ac, we needed to go back to the drawing board. Read More »
Tags: 802.11ac, access point, aggregation scheduler, antenna, AP, byte, Cisco, cpu, data plane, Enterprise, HD, HDX, high density, increased aggregation, modulation, multi-client, network, networking, packet scheduler, packets per second, performance, pps, qam, radio, scale, technology, wi-fi, wifi, wireless
Three years ago, when I blogged about the Cable Converged Access Platform (CCAP), current events involved whether it would be called “CMAP,” “CESAR,” or something else entirely. (So much clearer in hindsight!)
Last year, when I blogged about CCAP at The Cable Show, current events centered on phasing, and how to prepare plant and infrastructure for the unified QAMs of CCAP — while the gear itself was being architected and built.
For what was Phase 1, Read More »
Tags: cable, cable show, ccap, cox communications, ncta, ncta 2013, qam
The last time I blogged about CCAP, we were checking the online anagram universe for words one could make out of “CMAP” and “CESAR,” then two competing labels for the work of converging the QAM modulators used by digital voice, video and data services in cable.
Happily for me (because the anagram selections were abysmal), it settled out as what is now “CCAP” – the Cable Converged Access Platform. Watch for it to be a pretty hot topic at next week’s Cable Show — and not just because we announced a pretty incredible new downstream line card (the DS-384) related to it. Although…
CCAP matters at this year’s Cable Show for the same reason it mattered last year: Because consumer usage of broadband is off the hook, and cable operators need to stay ahead of that very tight curve, because narrowcast services are Read More »
Tags: ccap, qam, Service Provider, video, videoscape
By Mark Palazzo, VP/GM, Cable Access Business Unit, Cisco Systems
One of the more nuanced aspects of hard-core technological developments in the cable industry these recent months is the “CMAP v. CESAR” debate. Haven’t heard of it? Boiled way down, it’s a different set of viewpoints about the best way to migrate to a converged CMTS and universal edge QAM architecture, in conjunction with cable’s HFC (hybrid fiber-coax) plant migration.
To put this in historical context, cable operators “went digital” in phases. Digital video was first, followed by broadband data via cable modems, followed fairly shortly after by voice over IP. Operators use a form of modulation called “QAM” (quadrature amplitude modulation) to get video, data and voice signals over the plant to subscribing homes and businesses.
At issue was simple market timing: Digital video vendors built QAM products specifically to support video; broadband-side vendors built different QAM products, for high-speed data; and voice equipment vendors built QAM based TDM products for voice. The proprietary data and voice products where later replaced with the standardized DOCSIS CMTS platform. Read More »
Tags: cable, cmap, cmts, qam, Service Provider