From 16e05b0ed8e07cb0d9f3f9069190bfc8564b85b5 Mon Sep 17 00:00:00 2001 From: Hugh Ratsch Date: Tue, 28 Jan 2025 22:13:10 -0600 Subject: [PATCH] added ch 2 --- src/2-network-access.md | 82 +++++++++++++++++++++++++++++++++++++++++ src/SUMMARY.md | 1 + 2 files changed, 83 insertions(+) create mode 100644 src/2-network-access.md diff --git a/src/2-network-access.md b/src/2-network-access.md new file mode 100644 index 0000000..ce9a91b --- /dev/null +++ b/src/2-network-access.md @@ -0,0 +1,82 @@ +# Network Access + +This section focuses on configuring and verifying network access technologies, including VLANs, interswitch connectivity, spanning tree, wireless access, and network device management. + +## 2.1 VLANs + +VLANs (Virtual LANs) divide a physical network into multiple logical networks. This improves security, performance, and manageability. + +* **Normal Range VLANs:** VLANs with IDs from 1 to 1005. +* **Access Ports:** Connect end devices to the network. They are assigned to a specific VLAN. + * **Data VLANs:** Carry regular user traffic. + * **Voice VLANs:** Carry VoIP traffic and often have higher QoS priority. +* **Default VLAN:** VLAN 1 is the default VLAN on Cisco switches. It's generally recommended to change the native VLAN to a different VLAN for security reasons. +* **Inter-VLAN Routing:** Allows communication between different VLANs. This is typically done using a router or a Layer 3 switch. + +## 2.2 Interswitch Connectivity + +* **Trunk Ports:** Carry traffic for multiple VLANs between switches. +* **802.1Q:** A standard for tagging frames with VLAN information. +* **Native VLAN:** The untagged VLAN on a trunk port. + +## 2.3 Layer 2 Discovery Protocols + +* **Cisco Discovery Protocol (CDP):** Cisco proprietary protocol for discovering neighboring Cisco devices. +* **Link Layer Discovery Protocol (LLDP):** An industry-standard protocol for discovering neighboring devices. + +## 2.4 EtherChannel + +EtherChannel bundles multiple physical links into a single logical link, increasing bandwidth and providing redundancy. + +* **LACP (Link Aggregation Control Protocol):** A dynamic protocol for negotiating EtherChannel links. + +## 2.5 Rapid PVST+ Spanning Tree Protocol + +Spanning Tree Protocol (STP) prevents loops in a Layer 2 network. Rapid PVST+ is a Cisco enhancement to STP. + +* **Root Port:** The port on a non-root switch that has the lowest cost path to the root bridge. +* **Root Bridge:** The switch with the lowest bridge ID. +* **Port States:** + * **Forwarding:** The port is forwarding traffic. + * **Blocking:** The port is blocking traffic to prevent loops. +* **PortFast:** Immediately transitions an access port to the forwarding state. +* **Root Guard:** Prevents a port from becoming a root port. +* **Loop Guard:** Prevents loops caused by unidirectional links. +* **BPDU Filter:** Prevents BPDUs (Bridge Protocol Data Units) from being sent or received on a port. +* **BPDU Guard:** Puts a port in an error-disabled state if it receives a BPDU. + +## 2.6 Cisco Wireless Architectures and AP Modes + +Cisco wireless architectures include autonomous APs, lightweight APs (controlled by a WLC), and cloud-managed APs. AP modes include: + +* **Local Mode:** The AP acts as an autonomous AP. +* **FlexConnect Mode:** The AP can operate independently if the connection to the WLC is lost. +* **Monitor Mode:** The AP captures and analyzes wireless traffic. + +## 2.7 Physical Infrastructure Connections of WLAN Components + +WLAN components are connected using various physical interfaces and cabling: + +* **APs:** Connect to the network using Ethernet cables. +* **WLCs:** Connect to the network using Ethernet cables and may use LAG (Link Aggregation) for redundancy. +* **Access/Trunk Ports:** Used to connect APs and WLCs to the network. + +## 2.8 Network Device Management Access + +Network devices can be managed using various methods: + +* **Telnet:** Insecure remote access protocol. +* **SSH:** Secure remote access protocol. +* **HTTP/HTTPS:** Used for web-based management. +* **Console:** Direct access to the device using a console cable. +* **TACACS+/RADIUS:** Authentication, authorization, and accounting (AAA) protocols for centralized access control. +* **Cloud Managed:** Devices are managed through a cloud-based platform. + +## 2.9 Wireless LAN GUI Configuration + +Wireless LAN controllers provide a graphical user interface (GUI) for configuring: + +* **WLAN Creation:** Creating and configuring wireless networks (SSIDs). +* **Security Settings:** Configuring encryption protocols (WPA2, WPA3). +* **QoS Profiles:** Prioritizing different types of wireless traffic. +* **Advanced Settings:** Configuring radio settings, channel selection, and other advanced features. \ No newline at end of file diff --git a/src/SUMMARY.md b/src/SUMMARY.md index 8af6352..d19c89c 100644 --- a/src/SUMMARY.md +++ b/src/SUMMARY.md @@ -1,3 +1,4 @@ # Summary - [Chapter 1 Network Fundamentals](1-network-fundamentals.md) +- [Chapter 2 Network Access](2-network-access.md)