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Cisco Service Discovery Gateway – Enabling Zeroconf in Enterprise Networks

Cisco Service Discovery Gateway – Enabling Zeroconf in Enterprise Networks

I’ll admit it: I’m what others call an Apple fan boy. One of the many reasons for being one is the polished user experience and the ease-of-use of their products. One of the underlying technologies that enables the user to discover devices and services on the network is Zeroconf or, as Apple calls it, Bonjour.

Zeroconf consists of three major components:

  • Address auto configuration,
  • Naming –and–
  • Service discovery.

If your network doesn’t have a DHCP server or you haven’t statically assigned an IP address to your host, most operating systems will use an automatic private IP address. I’m not going into much detail on address auto configuration except that this is typically done using a technique called APIPA (Automatic Private IP Addressing) for IPv4 the host will use the famous 169.254.0.0/16 addresses or, in case of IPv6, by using link-local addresses only (FE80::/10) which has been designed into IPv6 as a basic functionality from day one. Also, naming is not of much of a concern in the context of this discussion. However, it is worth mentioning that Zeroconf names can contain Unicode characters and whitespace, which can make those names a lot more user friendly and meaningful contrary to pure DNS names.

The more interesting part, as it pertains to Zeroconf, is the service discovery. Read More »

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Route Redistribution – A thing of the past?

This week at CiscoLive Orlando, Cisco made two announcements around Enterprise Routing – Open EIGRP and EIGRP OTP. Originally announced at CiscoLive London, EIGRP has been opened to the community as an IETF Informational Draft “Open EIGRP”, Open EIGRP  provides vendors with technical information on EIGRP and the accumulation of 20 years of development and enhancements. With the publishing of this IETF Draft, vendors can now integrate EIGRP into their appliances and interop with Cisco.

On Tuesday, Cisco also announced a new innovation in Enterprise Routing; “EIGRP Over the Top” (or simply OTP).

EIGRP OTP

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Programmability and SDN are not the same

Network programmability means democracy, means freedom, freedom to program across all layers and entities, software or hardware – depending on your needs. Is SDN required to have network programmability? Not at all. Does the SDN architecture leverage network programmability? Yes, of course.  So, why do many people equate network programmability and SDN? Read More »

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What is a “Controller”? And how many do we need?

Thanks to SDN, the “Controller” word pops up in many network architecture discussions these days. In networking alone, we’re already surrounded by many “controllers” and we’re busy introducing more as we speak:  For example, Session Border Controllers or Wireless LAN Controllers have been around for quite some time, and have recently announced the OpenDaylight Controller, the Cisco XNC, or the Cloupia Unified Infrastructure Controller. So what is a “Controller” in networking terms, and how many do we need in emerging network architectures?

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VIRL Saves the Day!

One of the themes of my posts is that the overall ONE strategy, including virtualisation, would create an environment for network systems development that would meet the expectations of systems developers accustomed to the “enterprise” style of software development.

An enterprise systems developer expects the required systems resources for software development to be readily available for development and test purposes. When those resources constitute web application servers and databases, this is trivial with virtualisation, and generally unremarkable in today’s enterprise environments.

When those resources constitute expensive, high-end, routing and switching platforms, though, life is not that straightforward. A major part of a network engineer’s time is spent on obtaining, connecting and configuring network equipment for demonstration and test purposes. You can’t just try an idea out when it occurs to you, as the required network platforms often can’t be available when, and in the configuration, you want.

But imagine what you could do if those network resources were available at a click of a button. What if network engineers had the same capabilities as software engineers to create virtual environments of near perfect fidelity? Well, with the technology of the Virtual Internet Routing Laboratory (VIRL), that we are demonstrating at Cisco Live in Florida, that possibility is getting closer. Read More »

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