Troubleshooting Route Summarization in OSPF This section discusses a feature in OSPF called route summarization. The idea is that if there are contiguous ranges of addresses, instead of advertising every network, you can form a group of contiguous networks and summarize those networks in one, two, or fewer blocks and advertise those blocks. This feature helps reduce the size … [Read more...]
Troubleshooting OSPF Route Advertisement
Troubleshooting OSPF Route Advertisement This section discusses the problems related with OSPF route advertisement. OSPF is a link-state protocol. When it forms neighbor relationships, it exchanges the entire link-state database with its neighbor(s). If any database information is not shared with the neighbor, the link-state characteristics of OSPF will break. The most … [Read more...]
Building a Site-to-Site IPsec VPN Solution
Building a Site-to-Site IPsec VPN Solution Exploring the Basics of IPsec This section begins by identifying the characteristics of an IPsec VPN. You will learn about various protocols that make IPsec VPNs possible, including IKE protocols and the ESP and AH protocols. Although you can have a Cisco IOS router act as a VPN termination device, Cisco has other network devices … [Read more...]
Exploring PKI and Asymmetric Encryption
Exploring PKI and Asymmetric Encryption Understanding Asymmetric Algorithms Asymmetric algorithms support two of the primary objectives of any form of security, because their main objectives are confidentiality and authentication. To meet these objectives, these algorithms are based on much more complex mathematical formulas that require greater time to compute than symmetric … [Read more...]
Implementing Digital Signatures
Implementing Digital Signatures Examining Hash Algorithms For centuries everyone from kings to generals to college students has wanted to ensure the authenticity of their communications. In this section we will examine the role of hash algorithms in helping provide this assurance through the process of hashing. Along the way we will examine hash functions and learn about … [Read more...]
Designing a Cryptographic Solution
Designing a Cryptographic Solution Introducing Cryptographic Services To understand cryptographic services, first you must understand the science of cryptology, which in essence is the making and breaking of secret codes. Cryptology can be broken into two distinct areas: cryptography and cryptanalysis. Cryptography is the development and use of codes. Cryptanalysis is all … [Read more...]
Using Cisco IOS IPS to Secure the Network
Using Cisco IOS IPS to Secure the Network Examining IPS Technologies Although IDS and IPS perform similar functions, this section explores how these network security solutions differ. Various approaches to detecting and preventing an intrusion are discussed. This section also explores signatures and how they can trigger an alarm. This section concludes by discussing best … [Read more...]
Using Cisco IOS Firewalls to Defend the Network
Using Cisco IOS Firewalls to Defend the Network Exploring Firewall Technology Securing all aspects of your network can be a daunting task. For an organization with ecommerce, intranet, and extranet sites, as well as e-mail, this only adds to the complexity of the task. Of course, there are costs to providing a high level of security, in terms of both staff and equipment … [Read more...]
Exploring Secure Voice Solutions
Exploring Secure Voice Solutions Defining Voice Fundamentals This section begins by defining voice over IP and considering why it is needed in today’s corporate environment. Because voice packets are flowing across a data infrastructure, various protocols are required to set up, maintain, and tear down a call. This section defines several popular voice protocols, in addition … [Read more...]
Providing SAN Security
Providing SAN Security Overview of SAN Operations Organizations are producing ever-increasing amounts of data. A storage-area network (SAN) is an effective means to allow them to store and access this data in a secure fashion. This section examines the fundamentals of SAN operation and describes the technology behind these focused networks. It also examines attacks focused on … [Read more...]