CCNA – Operation of IP Data Networks 1.1

We kick off the CCNA series from the beginning. Operation of IP data networks is weighted as 5% in the CCNA RS blueprint. The first topic is:

1.1 Recognize the purpose and functions of various network devices such as routers, switches, bridges and hubs

Router

A router is a device that routes between different networks, meaning that it looks at the IP header and more specifically the destination IP of a packet to do forwarding. It uses a routing table which is populated by static routes and routes from dynamic protocols such as RIP, EIGRP, OSPF, ISIS and BGP. These routes are inserted into the Routing Information Base (RIB). The routes from different sources compete against each other and the best route gets inserted into the RIB. To define how trustworthy a route is, there is a metric called Administrative Distance (AD). These are some of the common AD values:

0          Connected route
1          Static route
20         External BGP
90         EIGRP
110        OSPF
115        ISIS
120        RIP
200        Internal BGP
255        Don't install

If a value of 255 is used, the route will not installed in the RIB as the route is deemed not trustworthy at all.

The goal Continue reading

Judge does not order Apple to disable security on encrypted device

Well, well, well…a federal magistrate of the U.S. District Court for the Eastern District of New York has so far refused to order Apple to disable security on a customer’s encrypted mobile device even though the government assured the judge that doing so “is not likely to place any unreasonable burden on Apple.”According to the court document (pdf), available on Cryptome which recently admitted to a leaking users’ IP addresses in a separate tech drama, the government filed a sealed application on Oct. 8; it asked the court “to issue an order pursuant to the All Writs Act,” and thereby force Apple “to assist in the execution of a federal search warrant by disabling the security of an Apple device that the government has lawfully seized pursuant to a warrant issued by this court. Law enforcement agents have discovered the device to be locked, and have tried and failed to bypass the lock.”To read this article in full or to leave a comment, please click here

HP and SanDisk join forces to create storage 1000x faster than NAND flash

HP and SanDisk are plotting new storage technology that could be 1,000 times faster than flash memory, though they’ll face some competition along the way.Details on the new technology are scarce, but the goal is to create a “universal memory” that serves as both long-term storage and RAM, the Wall Street Journal reports. The goal is to commercialize this technology some time between 2018 and 2020.Why this matters: Today’s computers offer RAM and storage separately, because the former is much more expensive and purges its data when the machine powers down. Programs and files are stored on flash memory, but during use they’ll load some data into RAM for faster short-term access. A single type of memory for both short- and long-term storage could boost a PC’s performance dramatically.To read this article in full or to leave a comment, please click here

As a private company, Dell-EMC will enjoy a freedom HP can only dream of

Dell's US$67 billion acquisition of EMC will give it access to a sales force notorious for its ability to "sell ice to eskimos," while EMC will gain a new foothold among mid-market customers. As a private entity, the combined result will face a freedom from market pressures that competitors such as HP can only dream of.Those are just some of the benefits that could follow from the deal announced early on Monday."This industry is undergoing a fundamental transformation," said Crawford del Prete, an executive vice president with IDC. "You can't navigate it with short-term business decisions."To read this article in full or to leave a comment, please click here

California governor vetoes bill punishing irresponsible drone users

After several incidents where irresponsible drone users interfered with firefighting planes, California looked poised to pass harsher penalties for the idiots who were endangering the planes. It seemed a no-brainer. Well, Governor Jerry Brown doesn't seem to have a brain.In three days, he signed a climate change bill, a gender pay equity law, a bill to combat racial profiling, and one legalizing assisted suicide. But he vetoed three bills that would have prohibited civilians from flying aerial drones over wildfires, schools, prisons, and jails.To read this article in full or to leave a comment, please click here

AWS re:Invent re:cap

rePlay

What a week. Some tech conferences I like, and others I love. Falling solidly in my "love" category, the Amazon team pulled off another great event with re:Invent 2015. Of course, the AWS product folks didn’t disappoint, either. (And neither did surprise re:Play party guest Zedd.)

We welcomed many hundreds of visitors to our booth during the three days. Over 200 shirts, many more Ansibulls, and every single sticker, luggage tag, and business card were gobbled up by excited Ansible users and Tower customers.

Perhaps the most entertaining part was to learn what people had to say:

“We heart Ansible.”
“Ansible is the only predictable thing about our environment.”
“DevOps? More like AnsibleOps.”
“You guys changed our lives.”
“I keep getting told I need to look at Ansible.”
“Thank you… just thank you.” (My personal favorite)

Certainly all bold statements for an IT orchestration tool. Even Network World joined in on the fun by naming Ansible one of the hottest products at re:Invent, thanks in part to our new IAM modules that simplify the setup and maintenance of IAM users, groups, keys, and policies.

The sentiments got me thinking. Seemingly, AWS is Continue reading

Making the Case for Building Scalable Stateful Services in the Modern Era

For a long time now stateless services have been the royal road to scalability. Nearly every treatise on scalability declares statelessness as the best practices approved method for building scalable systems. A stateless architecture is easy to scale horizontally and only requires simple round-robin load balancing.

What’s not to love? Perhaps the increased latency from the roundtrips to the database. Or maybe the complexity of the caching layer required to hide database latency problems. Or even the troublesome consistency issues.

But what of stateful services? Isn’t preserving identity by shipping functions to data instead of shipping data to functions a better approach? It often is, but we don’t hear much about how to build stateful services. In fact, do a search and there’s very little in the way of a systematic approach to building stateful services. Wikipedia doesn’t even have an entry for stateful service.

Caitie McCaffrey, Tech Lead for Observability at Twitter, is fixing all that with a refreshing talk she gave at the Strange Loop conference on Building Scalable Stateful Services (slides).

Refreshing because I’ve never quite heard of building stateful services in the way Caitie talks about building them. You’ll recognize most of the Continue reading

What Dell buying EMC means for VMware

With Dell acquiring EMC for a record $67 billion, it raises the question: What does this all mean for VMware and its customers?Officially, Dell says VMware will remain an independent publicly traded company. The wrinkle is that EMC owns 83% of VMware’s stock; and Dell is acquiring EMC.Forrester analyst Glenn O’Donnell says he expects the impact of the merger on VMware customers to be minimal. “You can basically look at this as some musical chairs at the high end,” he says. But other analysts say there could be significant opportunities for Dell to combine its hardware with VMware’s software.+MORE AT NETWORK WORLD: Dell acquires EMC for $67 billion | VMware CEO hits on network virtualization reality, feuding with Cisco & the EMC Federation's future +To read this article in full or to leave a comment, please click here

Worth Reading: Hybrid Infrastructure

Although industry experts anticipate a 44 percent annual growth in cloud-based workloads over the next several years, the reality is that despite rapid cloud adoption, many businesses will continue to have a significant part of their daily operations tied to physical infrastructure and its processes for many years to come. The Cloud is for everyone, but not for everything. — via the data center journal

The post Worth Reading: Hybrid Infrastructure appeared first on 'net work.

Google’s OnHub turns out to be part router, part Chromium OS computer

While Google cheerily advertises the 13 antennas packed into its new OnHub router, the company’s been less forthcoming about the software under the hood. Now that some hackers have rooted the high-tech Wi-Fi router, we have some clarity: OnHub appears to run a heavily-modified version of Chromium OS, the same browser-based software that powers Chromebook laptops and Chromebox desktops. The root method for OnHub first appeared on Exploitee.rs. It turns out that the router’s underside contains a hidden switch underneath one of its screws. This switch can boot OnHub into developer mode if you enter a specific keystroke, using a keyboard plugged into the router’s USB port. That keystroke is Ctrl + D, which is precisely what you’d use to enter developer mode in Chromium OS.To read this article in full or to leave a comment, please click here

Why Verizon’s ‘zombie cookies’ are scarier than ever

Like the Walking Dead lurching across your TV screen, Verizon's "zombie cookies" never give up. These hard-to-kill bits of code that track your mobile surfing habits are about to be shared with Verizon's newest acquisition, AOL, and that means additional advertisers will learn even more about you.Beginning in November, if you access the Web via Verizon’'s network, data on "your gender, age range and interests," (according to a Verizon FAQ page on its Relevant Mobile Advertising program) will be pushed to AOL's extensive network of advertisers.To read this article in full or to leave a comment, please click here

Why Verizon’s ‘zombie cookies’ are scarier than ever

Like the Walking Dead lurching across your TV screen, Verizon's "zombie cookies" never give up. These hard-to-kill bits of code that track your mobile surfing habits are about to be shared with Verizon's newest acquisition, AOL, and that means additional advertisers will learn even more about you.Beginning in November, if you access the Web via Verizon’'s network, data on "your gender, age range and interests," (according to a Verizon FAQ page on its Relevant Mobile Advertising program) will be pushed to AOL's extensive network of advertisers.To read this article in full or to leave a comment, please click here

Top 5 security threats from 3rd parties

 This vendor-written tech primer has been edited by Network World to eliminate product promotion, but readers should note it will likely favor the submitter’s approach.

From Target to Ashley Madison, we’ve witnessed how interconnections with third-party vendors can turn an elastic environment -- where devices, services and apps are routinely engaging and disengaging -- into a precarious space filled with backdoors for a hacker to infiltrate an enterprise’s network. Here are the top five threats related to working with 3rd parties:

Threat #1 - Shared Credentials. This is one of the most dangerous authentication practices we encounter in large organizations. Imagine a unique service, not used very frequently, requiring some form of credential-based authentication. Over time, the users of this service changes, and for convenience considerations, a single credential is often used. The service is now accessed from multiple locations, different devices and for different purposes. It takes just one clumsy user to fall victim to one {fill in the credential harvesting technique of your choice}, to compromise this service and any following user of that service.

To read this article in full or to leave a comment, please click here

Rule 11 is your friend

It’s common enough in the networking industry — particularly right now — to bemoan the rate of change. In fact, when I worked in the Cisco Technical Assistance Center (TAC), we had a phrase that described how we felt about the amount of information and the rate of change: sipping through the firehose. This phrase has become ubiquitous in the networking world to describe the feeling we all feel of being left out, left behind, and just plain not able to keep up.

It’s not much better today, either. SDNs threaten to overturn the way we build control planes, white boxes threaten to upend the way we view vendor relationships, virtualization threatens to radically alter the way we think about the relationship between services and the network, and cloud computing promises just to make the entire swatch of network engineers redundant. It’s enough to make a reasonable engineer ask some rather hard questions, like whether it’s better to flip burgers or move into management (because the world always needs more managers). Some of this is healthy change, of course — we need to spend more time thinking about why we’re doing what we’re doing, and the competition of the cloud Continue reading

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