Cisco Resources

STP was developed to prevent loops (aka, Switching loops or layer 2 loops) at layer 2 in a switched network with parallel links between switches, thus creating more than one path to a single destination. These loops, in turn, will create a much worst condition called a Broadcast Storm which is a result of broadcast, multi-cast and/or unknown-destination frames looping endlessly around the network, and this happens because of two main reasons; First, because switches will forward these frames out of every port except the receiving port (This is called Flooding) every single time they receive them. Second, at layer 2 (as opposed to layer 3) there is no Time To Live (TTL) field in the frames header, so frames will not “expire”. They will go around and around in a network until the network is shutdown or it fails.....READ MORE

The following table and associated description provides a brief overview of the malware samples, as well as an overview of the actions that Cisco took in response to those findings. The source of this information is internal analysis performed by Cisco forensics teams.....READ MORE

Dan Geer, chief information security officer at the venture capital firm In-Q-Tel and an adviser to U.S. intelligence agencies, speaking to a conference in Cambridge, Mass., more than a year ago, said most routers are almost comically insecure, given that they have, “drivers and operating systems amounting to snapshots of the state of Linux, plus the lowest-end commodity chips extant at the time of the router’s design.”....... READ MORE

Now with HyperFlex, Cisco takes firmer control of its convergence destiny. The product is built around a bundle of Cisco hardware and software, including UCS for compute and storage, UCS Fabric Interconnects for networking, and UCS Manager for management.....READ MORE

This article will analyze the states OSPF routers go through during OSPF neighbor discovery and adjacency process. We examined in detail each OSPF State including: Down state, Attempt state, Init state, 2-way state, Exstart state, Exchange state, Loading state and Full state.....READ MORE

To truly adopt an open workspace, there is more pressure on the wireless network to not only use high-performance Wi-Fi, but more intelligent wireless connectivity. By its nature, open workspaces employ open floor plans which leave less areas for cable drops, making Wi-Fi the primary means of access. Employees are using more collaborating video from large systems—even on their mobile devices—and new, non-user devices are all increasingly attaching to the wireless network.....READ MORE

This article explained OSPF Link State Update (LSA) packets and showed how they contain Link State Advertisements (LSAs). We also analyzed OSPF LSU & LSAs packet structure and explained each field in an OSPF LSA packet. Finally, we spoke about the most common LSA Types, router origin type (ABR, ASBR, DR etc), their function and Areas affected. Read more on OSPF by visiting our OSPF Section.....READ MORE

Additionally, simply securing a WLAN through the use of authentication mechanisms and encryption isn't enough. You have to be concerned with who you are granting access to and what they can access. The identification and segmentation of employees, contractors, and guests is a great way to protect the network.....READ MORE

Most wireless networks have neighboring tenants occupying the same 2.4 GHz frequency band. When two or more APs are on the same channel, they operate within the same contention domain....READ MORE

Since its birth in 1999, the Cisco Catalyst 6500 Series has grown considerably in available options and bandwidth potential. The introduction of its cousin in 2013, the Cisco Catalyst 6800, is further proof of its staying power. This product line was designed to ease users into an upgrade with some degree of adaptability with existing infrastructure, including compatibility with 6500 series blades, greater throughput potential, and options for Instant Access satellite switches and newer technology....READ MORE

With CMX Cloud and the new DNA, Santana Row can gain real-time insights and deliver relevant experiences to get customers to stay a little longer and keep them coming back....READ MORE

In this article and video, I want to share a configuration change that I recommended to the customer in lieu of a firewall. Of course nothing is a proper substitute for a real firewall, but sometimes we need to make do with what we have. There are quite a few documents out there explaining how to harden your router. This tip protects you specifically from ICMP attacks or ping flooding....READ MORE

If the protocols are used within a network, they are called IGP (Interior Gateway Protocols). If the protocol is used between the networks, it is called EGP (Exterior Gateway Protocols). IGP protocols include RIP, EIGRP, OSPF and IS-IS. And today only EGP protocol is BGP.....READ MORE

So here are some of the basic steps that I think you should consider when configuring a Cisco device facing an untrusted network, assuming you may need these protocols on the interior:......READ MORE

If you are locked out of your 3850 switch and need to perform Password recovery on a Cisco Catalyst 3850 switch this short tutorial will guide you along the way. You will need - One Cisco Catalyst 3850 switch or switch stack which you have forgotten or do not know the password for.....READ MORE

The organizations of all sizes and ages must learn to disrupt and reinvent themselves – strategically and culturally – before they are disrupted to the point of extinction. Remember the likes of Kodak, Blackberry, Blockbuster, Borders, Nokia and Circuit City, which either resisted fast innovation or couldn’t fully embrace it?.......READ MORE

Cisco is introducing a new Global Cybersecurity Scholarship program and enhancing its security certification portfolio. Cisco will invest $10 million over a two-year period to establish a scholarship program with the specific goal of increasing the cybersecurity talent pool. Through the program, Cisco will offer training, mentoring, and certification aligned with the security operations center analyst role.............READ MORE

In recent years, we’ve seen Cisco tightly integrate separate security technologies such as Intrusion Prevention Systems (IPS) and Intrusion Detection Systems (IDS) within the ASA Firewall appliances in the form of hardware module add-ons (older 5500 series & newer 5500-X series) and, recently, software modules supported only by the newer ASA 5500-X series security appliances..........READ MORE

Smartphone traffic will exceed PC traffic by 2020. While in 2015, the relative percentages were 8 percent of total IP traffic for smartphones versus 53 percent for PCs, by 2020, the PC percentage will have dropped to 29 percent while smartphones will account for 30 percent.......READ MORE

And innovation is no longer the domain of solo inventors alone in their garages. With today’s complex technology, it requires co-innovations involving collaborations of all kinds focused on the same goals. Our experience shows that game-changing ideas can come from anywhere, and anyone.......READ MORE