Problem solve

Problem solve

Get help with specific problems with your technologies, process and projects.

• How do you assign a default gateway?

  Find out the command you need to run to assign a default gateway in this response from our routing and switching expert, Sudhanshu Gupta. Continue Reading

• Can you convert a Layer 3 switch to Layer 2?

  See how a Layer 3 switch can convert to a Layer 2 switch, in this expert response. Continue Reading

• At what circuit utilization percentage should I increase bandwidth?

  How do you know when to increase your bandwidth? Find out from WAN optimization expert Dr. David Hughes. Continue Reading

• Cisco router ISDN configuration

  Learn how to configure your Cisco router to work with Integrated Services Digital Network (ISDN). This tip teaches you Cisco routers' basic ISDN configuration, demand dial routing and demonstrates real-case scenarios for your routing connection. Continue Reading

• Are high-gain antennas needed on both AP and client sides?

  See if you need a high-gain antenna on both the AP and client side to boost wireless range and signal quality. Wireless expert Lisa Phifer elaborates on the metrics and reasoning. Continue Reading

• What is FEC in MPLS?

  Learn what Forwarding Equivalence Class (FEC) is and how it works with Multiprotocol Label Switching (MPLS).Continue Reading

• What are TCP Wrappers? How do they work?

  Network security expert, Puneet Mehta, explains TCP Wrappers and how they work in this Ask the Expert.Continue Reading

• What is layered defense approach to network security?

  Learn what the layered defense approach to network security is in this expert response.Continue Reading

• Frame relay, ATM, and Gigabit Ethernet pros and cons

  Frame relay, ATM, and Gigabit Ethernet have pros and cons for basing network infrastructure off of, according to our networking fundamentals expert.Continue Reading

• How do you check if TCP/IP is installed on the system?

  Understand the TCP/IP stack and how to check if it is installed on your system in this networking fundamentals expert response.Continue Reading

• Troubleshoot network problems with Network Monitor

  Learn how Network Monitor can be used to troubleshoot various types of network problems in this tip from WindowsNetworking.com.Continue Reading

• How do we control who gets our wireless network's free Internet access?

  Learn how to control access to your wireless network's free Internet.Continue Reading

• Secure Cisco routers against IOS flaw attack

  Learn how to secure Cisco routers against the recently announced Cisco IOS flaw, which could be exploited by hackers. Find out how to determine which routers are affected and ways to protect yourself from this vulnerability, including steps to ...Continue Reading

• Network analysis -- Enhancing security assessments

  Network security assessment doesn't have to rely on expensive automated tools. In this tip, learn how to use data from freely available tools to produce a comprehensive view of network security.Continue Reading

• To renew my CCNP, which exam should I take?

  Learn what test you need to take to renew your CCNP from Cisco certification expert David Minutella.Continue Reading

• What protocol works on all layers of OSI?

  Learn what protocol, if any, works on all layers of OSI in this expert answer.Continue Reading

• How do routers and switches differ in the OSI model?

  Learn the difference between a switch and a router in relation to the OSI model in this Ask the Expert.Continue Reading

• How to block some users from the Internet while allowing others

  Learn how to block certain users from the Internet while allowing others on the same LAN in this expert response with enterprise security expert Michael Gregg.Continue Reading

• Are Linux Professional Institute (LPI) certifications good for a networking career?

  See if Linux Professional Institute (LPI) certifications will further your networking career in this expert response with our training and certification expert, Ed Tittel.Continue Reading

• Do sandstorms, too much heat, and strong winds affect Wi-Fi connections?

  How much does weather affect Wi-Fi? Wireless networking expert Lisa Phifer explains how sandstorms, too much heat and strong winds might affect your connection in this Q&A.Continue Reading

• Where should I place my cable modem?

  Learn how cable modem placement will affect your wireless network connection, in this expert response with Lisa Phifer.Continue Reading

• Operations support systems: Fundamentals of working with OSS

  Operations support systems (OSSs) are a stalwart of the telecom industry, but have been experiencing significant changes of late. Learn about the major types of OSSs and how technology and business changes are affecting them.Continue Reading

• Fixed mobile convergence: Understanding the landscape

  Fixed mobile convergence (FMC), the convergence of wired and wireless technologies into a single solution, is explained in this tip.Continue Reading

• Implementing video on demand

  Video on demand (VoD) implementation best practices are discussed, as well as VoD service, delivery and management models.Continue Reading

• What is the difference between VPN and VPN pass-through?

  In this Q&A, our VPN expert describes the difference between a basic VPN and VPN pass-through, a feature often found in small business Internet gateway devices.Continue Reading

• Ethernet as a service: Best practices for delivery

  Ethernet services can offer providers many benefits as well as the opportunity to lead customers into the managed services space. This tip offers best practices for providing Ethernet as a service.Continue Reading

• Using VRFs to provision customer traffic

  A virtual routing and forwarding (VRF) instance can allow network paths to be segmented without using multiple devices. Learn simple VPF configuration in this article.Continue Reading

• How many wireless devices can connect to an 802.11g access point?

  Learn how many wireless devices can connect to an 802.11G access point (AP) in this expert response with Lisa Phifer.Continue Reading

• To evaluate network management, what criteria is there?

  What are the criteria for evaluating how efficient your network management is? Find out in this expert response with Lindi Horton.Continue Reading

• Cisco CCIP MPLS certification: Introduction

  Learn skills required for the MPLS portion of the Cisco CCIP certification. These skills are tested in the CCIP 642-611 -- Implementing Cisco MPLS Exam.Continue Reading

• Optical networks: Metro network design best practices

  Optical networks in metro areas are being affected by many factors, including whether to use SONET, WDM or Ethernet, as well as the services, such as IPTV, that will be supported. Find out best practices for sifting through the complexity and ...Continue Reading

• Can I set up a VPN on my wireless router?

  Learn about the difference between functions in a consumer and pro-sumer cable modem and how to set up your VPN on your wireless router, in this Q&A.Continue Reading

• To set up a VPN server, do you need two NIC cards?

  To set up a VPN server, do you need two NIC cards? Find out the answer to this and how to fix disconnects in this Q&A with Sampath Ramaswami.Continue Reading

• Fiber-optic networks: Access network design

  Fiber-optic technology in access networks is expanding due to the demand for broadband in consumer environments. Learn about the pros and cons of FTTX and passive optical networking (PON) systems.Continue Reading

• How do I connect to our VPN with authentication ID?

  Learn how to connect wireless laptops to your VPN using a SecurID authentication and Nortel Contivity VPN gateway in this Q&A with wireless expert Lisa Phifer.Continue Reading

• Point-to-multipoint MPLS

  Learn how point-to-multipoint MPLS benefits video distribution and data that requires highly scalable and reliable transport.Continue Reading

• Understanding MPLS network components

  MPLS network components are explained from a service provider's viewpoint in this tip.Continue Reading

• Best practices for flexible project plans

  Flexible project plans for network service delivery are developed through proper planning, communication between the groups involved, and a well developed contingency plan.Continue Reading

• Network management and troubleshooting in the multimedia network

  Network management in a multimedia service provider network creates a stable framework for service delivery that will provide customers with good experiences for voice, data and video services under normal conditions. The main areas involve capacity...Continue Reading

• Configuring MPLS and VRF -- Cisco CCIP MPLS certification: Lesson 6

  Virtual Routing and Forwarding (VRF) is a key component of Layer 3 MPLS VPNs. It enables PE routers to appear to be many routers to the customer edge (CE) routers. The provider edge (PE) router will maintain separate and distinct routing tables for ...Continue Reading

• Label imposition -- Cisco CCIP MPLS certification: Lesson 4

  Label imposition, the process by which labels are assigned to packets, is examined in the fourth tip in a series that will help you learn skills required for the MPLS portion of the Cisco CCIP certification. These skills are tested in the CCIP 642-...Continue Reading

• Configuring MPLS -- Cisco CCIP MPLS certification: Lesson 5

  In addition to understanding MPLS theory, you must be able to configure routers for MPLS in order to pass the CCIP 642-611 - Implementing Cisco MPLS Exam. The configuration can apply to customer edge (CE) routers, provider edge (PE) routers or ...Continue Reading

• Understanding IMS (IP Multimedia Subsystem)

  IMS (IP Multimedia Subsystem) is an emerging architectural framework, based on SIP and IP, for offering multimedia and VoIP services, as well as fixed mobile convergence.Continue Reading

• Stop simultaneous connections to corporate LANs and external Wi-Fi networks

  How can you stop simultaneous connections to corporate LANs and external Wi-Fi networks? Find out from wireless expert Lisa Phifer in this Ask the Expert.Continue Reading

• Using Ethernet as carrier backbone transport

  Carrier Ethernet is making progress as a backbone transport technology, but there are challenges that must be addressed. The main issues, including maintaining scalability in large Ethernet networks, providing QoS to applications, and improving ...Continue Reading

• Optical networks: Core network design best practices

  Core optical network design must take into consideration network requirements specific to the core, including a high degree of aggregation, low reconfigurability, and large geographic scope, while confronting such challenges as router adjacency, ...Continue Reading

• Network monitoring essentials for service provider networks

  Network monitoring in service provider networks involves different tools, including systemic, end-to-end, device-level, and high- and low-level approaches. Learn about the pros and cons in this tip.Continue Reading

• Service provider billing system fundamentals

  Billing systems for service providers vary considerably in their focus and complexity. This tip looks at the fundamentals of working with billing systems.Continue Reading

• Service provider network management systems essentials

  Service provider network management systems are discussed, including their main goals: multi-vendor, multi-device access through a uniform interface, fault correlation and filtering, and end-to-end provisioning and management.Continue Reading

• DNS monitoring: If it's slow, everything is slow

  Techniques for monitoring DNS performance, and the impact on applications when it is not performing properly, are explored in this tip.Continue Reading

• ISDN protocols, components and router options

  Integrated Services Digital Network (ISDN) provides for digital transmission over ordinary telephone copper wire as well as over other media uses. In this continuation of his tip on ISDN implementation, Chris Partsenidis discusses the OSI Layers, ...Continue Reading

• TCP/IP troubleshooting: A structured approach -- Using Netdiag.exe

  Limitations of the Repair feature of Windows network connections can be overcome by using Netdiag.exe, a network connectivity troubleshooting tool that is part of the Windows Support Tools. Netdiag runs a more extensive series of tests than the ...Continue Reading

• VPN security: Hiding in plain sight, using network encryption

  Sensitive data in transit is subject to hacking attacks unless you protect it using some type of encryption. In this tip from Burton Group analyst Jeff Young, learn how network encryption using SSL, IPsec or other types of VPNs can keep your company...Continue Reading

• Dynamic routing essentials

  Learn how dynamic routing works and the most important routing protocols -- OSPF, EIGRP, RIP and BGP -- as well as how to configure them.Continue Reading

• To practice my CCNA, what equipment do I need?

  Learn what equipment you need to set up a home lab to practice for your CCNA in this Q&A with Cisco certifications expert David Minutella.Continue Reading

• How can I define the layered approach to protocols?

  Learn what the network security advantages are in the layered approach to protocols and how to define the layered approach protocol, in this Q&A with Michael Gregg.Continue Reading

• MPLS traffic engineering essentials

  MPLS (Multi-protocol Label Switching) traffic engineering basics are presented in this tip.Continue Reading

• Border Gateway Protocol (BGP) troubleshooting: Advanced approach

  This tip on troubleshooting Border Gateway Protocol (BGP) takes an advanced approach and details how to work with Internet service provider (ISP) networks.Continue Reading

• Do stateful packet-filtering firewalls have vulnerabilities?

  Learn what types of attacks stateful packet-filtering firewalls are vulnerable to in this Q&A with security expert Puneet Mehta.Continue Reading

• Border Gateway Protocol (BGP) troubleshooting: Simple approach

  In BGP troubleshooting, a structured approach can quickly lead you from initial problem diagnosis to the solution. This article focuses on a simple scenario with a single BGP-speaking router in your network.Continue Reading

• Introduction to Border Gateway Protocol (BGP)

  Border Gateway Protocol (BGP) is the routing protocol that makes the Internet work. This tip explains how BGP works.Continue Reading

• Is IT a good, safe career choice?

  Is IT a safe career choice? Read training and certification expert Ed Tittel's response to this query.Continue Reading

• How does any certification expire if a degree never does?

  Why does a certification expire? View this Q&A debating the reasons for network certification expirations.Continue Reading

• Virtual routing and forwarding (VRF) extends virtual networks

  Virtual networks are the backbone of virtual systems, linking the servers and storage that together constitute the virtual system. But virtual networks -- and therefore virtual systems -- are often limited to a single facility. Virtual routing and ...Continue Reading

• Understanding the ISDN standard

  Integrated Services Digital Network (ISDN) is a digital telephone standard designed to replace analogue connections by utilizing ordinary copper wires that are used in standard analogue telephone systems. Learn how Integrated Services Digital ...Continue Reading

• Managing Windows networks using scripts -- The basics

  Learning to use scripts can make the life of a network administrator a lot easier by allowing you to automate daily administration tasks. This tip begins a series on using scripts to manage Windows networks.Continue Reading

• What are the routing differences between IPv4 and IPv6?

  Between IPv4 and IPv6, find out how routing differs, in this Q&A with Silvia Hagen.Continue Reading

• Can I connect WLAN and LAN clients using 802.1x and EAP?

  Learn how to connect wireless and wired LAN clients using 802.1x and EAP with a workgroup instead of an Active Directory Domain in this Q&A with Lisa Phifer.Continue Reading

• Why can't my phone connect to the wired LAN?

  Learn why your 802.11g-enabled phone can connect to the Internet through a Lynksys router but not to your wired LAN, in this Q&A with Lisa Phifer.Continue Reading

• Is my hotspot provider vulnerable to MAC address spoofing?

  In this Q&A with wireless networking expert Lisa Phifer, see if your hotspot provider is vulnerable to MAC address spoofing when it uses Web portal to charge customers for wireless access.Continue Reading

• Configure Cisco wireless bridges for point-to-point networking

  Point-to-point wireless bridging is ideal for many business networks. In this tip, learn how point-to-point wireless bridging can help you, the pros and cons of using it, and the configuration of the Cisco wireless bridges that make it work. The ...Continue Reading

• How do I block MAC addresses from my DHCP server?

  Learn how to block MAC addresses on your network from getting any IP addresses off your DHCP server, in this expert response with security expert Puneet Mehta.Continue Reading

• TCP/IP troubleshooting: A structured approach -- Repairing network connections

  Learn how the Repair feature works for repairing network connections on Windows platforms in this tip from the WindowsNetworking.com series on TCP/IP troubleshooting.Continue Reading

• What causes packet loss across the WAN, and how can I tell when it affects application behavior?

  Learn what causes packet loss across a WAN, plus how you might be able to tell when packet loss is affecting your network's application behavior, in this Q&A with Dr. Hughes.Continue Reading

• How does a Layer 3 switch work in a network?

  Learn how a Layer 3 switch works in a network, in this Q&A with routing and switching expert Sudhanshu Gupta.Continue Reading

• How do I connect my VLANs to the Internet using NAT and the appropriately configured ACL?

  Confused about using NAT and configuring ACL? Learn how to connect your VLANs to the Internet over a router with sub-interfaces already defined.Continue Reading

• OSI: Securing the Stack, Layer 8 -- Social engineering and security policy

  Network security is essential at every layer of the OSI model, including the mythical eighth layer, where users interact with technology. Since hackers can use social engineering to exploit people, it is important to train your users and implement ...Continue Reading

• Reduce branch office threats in 10 steps

  Many organizations host business-critical applications in branch offices, but doing so exposes them to many new threats. Here we examine the potential threats to your branch offices and discuss 10 surefire ways to reduce or mitigate them.Continue Reading

• What is the advantage of frame relay over leased lines?

  Learn about data transmission over leased lines in this expert response about frame relay.Continue Reading

• Can you hook a Cisco IP phone to a wireless access point connection?

  Find out if you can hook a Cisco IP phone to a wireless access point connection in this Q&A with Carrie Higbie.Continue Reading

• What is the relationship between cable frequency and bandwidth?

  How does bandwidth relate to cable frequency? Find out from infrastructure expert Carrie Higbie, in this response.Continue Reading

• Wireless Internet access -- 3G vs. Wi-Fi

  Most road warriors have just two truly viable alternatives for wireless Internet access: 3G and Wi-Fi. In this tip, Lisa Phifer covers the pros and cons of 3G and Wi-Fi for coverage, convenience, capacity, control and cost.Continue Reading

• TCP/IP troubleshooting: A structured approach -- Troubleshoot routing tables

  Learn how routing tables work and how to troubleshoot routing problems in Windows-based networks in this tip courtesy of WindowsNetworking.com.Continue Reading

• Troubleshooting a DHCP server

  Learn how to troubleshoot a DHCP server to discover why it might fail to lease IP addresses and the solutions to those problems in this tip.Continue Reading

• How can I connect two wireless devices wirelessly via a router and an access point?

  WLAN expert Stephen Kim answers how to connect two wireless devices wirelessly via a router and an access point in this Q&A.Continue Reading

• Why does my event log show the client associate then disassociate, when I try to connect wirelessly?

  What does it mean when your event log shows the client associate then dissassociate? Learn how to connect wirelessly with expert Stephen Kim's advice.Continue Reading

• Will WEP and MAC address filtering protect our WLAN from hackers?

  Find out if you're doing enough to protect your WLAN against wireless hackers in this Q&A with Lisa Phifer.Continue Reading

• Should I start my networking career with Voice over IP, network security, or SANs?

  Learn what long term plan would advance your budding networking career, in this expert response with certification and training expert Ed Tittel.Continue Reading

• What causes my overseas VPN connection to slow during the day?

  Learn what slows connectivity for a VPN overseas during particular times of day, in this Q&A with VPN expert Sampath Ramaswami.Continue Reading

• What equipment do I use to connect two LANs in different cities? What are the steps?

  How do you connect two LANS from different cities? VPN expert Sampath Ramaswami notes the steps to be taken, in this Q&A.Continue Reading

• Can a machine with a single DNS name have multiple addresses?

  Can a machine with a single DNS name have multiple addresses? Learn from networking fundamentals expert Chris Partsenidis in this expert response.Continue Reading

• QoS classification and marking for VoIP infrastructures

  QoS for VoIP requires classification and marking as an essential component for establishing a reliable infrastructure.Continue Reading

• Understanding wireless antennas -- Part 2

  Upgraded antennas can improve wireless LAN performance, reach and security.Continue Reading

• What is network latency?

  Learn what network latency is in this expert response.Continue Reading

• What is the difference between online backup and offline backup?

  What is the difference between online backup and offline backup? Find out from SearchNetworking.com's networking help desk expert, Amy Kucharik.Continue Reading

• What's the difference between patches and service packs?

  In this Q&A with Amy Kucharik, learn what the difference is between a patch and a service pack.Continue Reading

• How routers work

  Routers are essential to carrying network traffic, but how do they work? In this tip, you'll get perspective on how routing fits into the OSI model. You'll also learn how routers use routing tables to direct IP packets, find the best route to a ...Continue Reading

• How can I limit the number of MBs each user downloads?

  Learn about rate limiting from network administration expert Lindi Horton, in this response.Continue Reading

• QoS components: A closer look

  A large component to a successful voice over IP (VoIP) infrastructure is effectively deploying a quality of service (QoS) model. QoS components entail classification and marking, congestion management, congestion avoidance, policing and shaping, and...Continue Reading

• When do you use a straight-through patch cable, and when do you use a crossover cable?

  Learn when to use a straight-through patch cable and when to use a crossover cable in this Q&A with infrastructure expert Carrie Higbie.Continue Reading