Archive

Category Archives for "Networking"

Worth Reading: Cutting through the segment routing hype

Segment Routing (SR) is a new traffic-engineering technology being developed by the IETF’s SPRING Working Group. Two forwarding plane encapsulations are being defined for SR: Multiprotocol Label Switching (MPLS) and IPv6 with a Segment Routing Extension Header. This article provides some historical context by describing the MPLS forwarding plane and control plane protocols, explains how Segment Routing works, introduces the MPLS-SR forwarding plane, and shows how the SR control plane is used. Finally, the article compares SR with legacy MPLS systems, and identifies its unique merits. —The IETF Journal

The post Worth Reading: Cutting through the segment routing hype appeared first on rule 11 reader.

On the ‘web: Is it really simpler?

Simplification is the metabuzzword overlaying the networking world today. For instance, Software Defined Wide Area Networks (SD-WANs), which propose to reduce the complexity of the enterprise wide area network, particularly the network connecting to the many thousands of remote sites many enterprises operate, by replacing MPLS and private line services purchased from service providers, with services that operate over the top of “plain jane Internet” connectivity. A second area where network operators are simplifying is by purchasing pre-integrated stacks of compute, storage, and networking, in a single rack, and controlled through a single GUI—a form of hyperconvergence. A third area is in the large amounts of interest in deploying Software Defined Networks (SDNs), which are being promoted based on the simplifications possible from removing “complex” distributed control planes from the network. There are three questions network engineers should ask in response to the simplification metabuzzword, however. —Tech Target

The post On the ‘web: Is it really simpler? appeared first on rule 11 reader.

BrandPost: Why An Intelligent WAN Edge Solution Is Key To Branch Office Success

The concept of the “thin branch” enabled by simplifying infrastructure has been around for as long as there have been branch offices. Branch offices are typically a microcosm of the company headquarters, but without the necessary IT staff to run them. It’s common to find a myriad of network and security equipment in a branch including a router, firewall, WAN optimizer, VPN concentrators, along with almost anything else you can think of. This, of course, results in an operational nightmare as network administrators must deal with multiple devices in dozens, hundreds or even thousands of branch locations. In small networks it can be extremely challenging to track all the different hardware components and related software versions across the various locations. In large networks, this task is impossible as the number of possible combinations of hardware and software grows exponentially in relation to the number of locations.To read this article in full or to leave a comment, please click here

Worth Reading: ISPs simplifying customer IPv6 addressing

One of the main issues for an ISP planning to deliver IPv6 services is to decide how to address the customers. In a generic way, we could say that the first thing to do for any IPv6 deployment is the complete network addressing plan, even before obtaining your addressing space from your Regional Internet Registry (RIR), so you get it right from the very beginning. In the case of corporate customers, generally nobody doubts that they should receive a /48 IPv6 GUA (Global Unicast Address) at every end-site, and of course, those prefixes should be persistent (often called static) to each customer. —APNIC

The post Worth Reading: ISPs simplifying customer IPv6 addressing appeared first on rule 11 reader.

Arista eAPI

The sFlow and eAPI features of EOS (Extensible Operating System) are standard across the full range of Arista Networks switches. This article demonstrates how the real-time visibility provided by sFlow telemetry can be combined with the programmatic control of eAPI to automatically adapt the network to changing traffic conditions.

In the diagram, the sFlow-RT analytics engine receives streaming sFlow telemetry, provides real-time network-wide visibility, and automatically applies controls using eAPI to optimize forwarding, block denial of service attacks, or capture suspicious traffic.

Arista eAPI 101 describes the JSON RPC interface for programmatic control of Arista switches. The following eapi.js script shows how eAPI requests can be made using sFlow-RT's JavaScript API:
function runCmds(proto, agent, usr, pwd, cmds) {
  var req = {
    jsonrpc:'2.0',id:'sflowrt',method:'runCmds',
    params:{version:1,cmds:cmds,format:'json'}
  };
  var url = (proto || 'http')+'://'+agent+'/command-api';
  var resp = http(url,'post','application/json',JSON.stringify(req),usr,pwd);
  if(!resp) throw "no response";
  resp = JSON.parse(resp);
  if(resp.error) throw resp.error.message;
  return resp.result; 
}
The following test.js script demonstrates the eAPI functionality with a basic show request: 
include('eapi.js');
var result = runCmds('http','10.0.0.90','admin','arista',['show hostname']);
logInfo(JSON.stringify(result));
Starting sFlow-RT: 
env "RTPROP=-Dscript.file=test.js" ./start.sh
Running the script generates the following output:
2017-07-10T14:00:06-0700  Continue reading

67% off BioShock: The Collection for PlayStation 4 – Deal Alert

Return to the cities of Rapture and Columbia and experience the award-winning BioShock franchise like never before. BioShock: The Collection retells the epic journeys of the BioShock universe beautifully remastered in 1080p. BioShock: The Collection contains all single-player content from BioShock, BioShock 2, and BioShock Infinite, all single-player add-on content, the 'Columbia’s Finest' pack, and Director’s Commentary: Imagining BioShock, featuring Ken Levine and Shawn Robertson. The list price for the PlayStation 4 version has been reduced 67% to just $19.99. XBox One and PC versions have been discounted as well. See this deal on Amazon.To read this article in full or to leave a comment, please click here

37% off DYMO LabelWriter Twin Turbo Label Printer and Mailing Scale – Deal Alert

This label maker from Dymo is an all-in-one kit with everything you need to address, weigh and stamp your mail. Thermal printing technology is silent and never needs ink, toner, or ribbons. 300 dpi resolution 55 labels per minute print speed. Includes label printer, scale, 1 roll of 200 DYMO Stamps postage labels and 1 roll of 130 DYMO address labels, as well as a 2-year limited manufacturer warranty. This desktop mailing solution averages 4 out of 5 stars from over 720 people on Amazon (read reviews), there the typical list price has been reduced 37% from $190 down to $119.59. See this deal now on Amazon.To read this article in full or to leave a comment, please click here

Cisco’s M5 UCS servers take intent-based approach to data center

It's not the server -- it's the system. That's the word from Cisco as it rolls out its new, M5 generation Unified Computing System rack and blade servers, triggered by Intel's release of the Xeon Scalable Processor platform.Cisco's new servers use the Xeon Scalable processors -- unveiled Tuesday in New York -- to fuel performance as well as increase server density and throughput.  But the value in the UCS product family lies in how the hardware works with configuration management and optimization software to make data centers run at peak efficiency, company officials say.To read this article in full or to leave a comment, please click here

Cisco’s M5 UCS servers take intent-based approach to data center

It's not the server -- it's the system. That's the word from Cisco as it rolls out its new, M5 generation Unified Computing System rack and blade servers, triggered by Intel's release of the Xeon Scalable Processor platform.Cisco's new servers use the Xeon Scalable processors -- unveiled Tuesday in New York -- to fuel performance as well as increase server density and throughput.  But the value in the UCS product family lies in how the hardware works with configuration management and optimization software to make data centers run at peak efficiency, company officials say.To read this article in full or to leave a comment, please click here

Cisco’s M5 UCS servers take intent-based approach to data center

It's not the server -- it's the system. That's the word from Cisco as it rolls out its new, M5 generation Unified Computing System rack and blade servers, triggered by Intel's release of the Xeon Scalable Processor platform.Cisco's new servers use the Xeon Scalable processors -- unveiled Tuesday in New York -- to fuel performance as well as increase server density and throughput.  But the value in the UCS product family lies in how the hardware works with configuration management and optimization software to make data centers run at peak efficiency, company officials say.To read this article in full or to leave a comment, please click here

When is a Connected Route Not Used?

I ran into this situation on a recent project and thought it would make an excellent question on an exam. It could be worded something like this:

What is the behavior of a router or Layer 3 switch when a dynamic route is learned that partially overlaps with a directly connected network?

a. The router reboots
b. The network reboots
c. That’s um-possible
d. None of the above

The answer, of course, is “d” but the specifics of what does happen is what’s interesting. First, this is the scenario I’m trying to describe in the question above:

R12#show ip route
...
Gateway of last resort is not set

      10.0.0.0/8 is variably subnetted, 6 subnets, 3 masks
D        10.1.14.0/24 [90/1024640] via 123.1.1.14, 00:14:37, Ethernet0/1
C        10.10.10.0/24 is directly connected, Ethernet0/0
L        10.10.10.12/32 is directly connected, Ethernet0/0
D        10.10.10.64/26 [90/1024640] via 123.1.1.14, 00:14:05, Ethernet0/1

R12 has a directly connected network 10.10.10.0/24 on its e0/0 interface. It has also learned a route for 10.10.10.64/26 via an EIGRP neighbor on its e0/1 interface. We can see both networks Continue reading

LockPoS Joins the Flock

While revisiting a Flokibot campaign that was targeting point of sale (PoS) systems in Brazil earlier this year, we discovered something interesting. One of the command and control (C2) servers that had been dormant for quite some time had suddenly woken up and started distributing […]
1 … 1,667 1,668 1,669 1,670 1,671 … 3,411