Network Time Protocol (NTP) is a protocol designed to time-synchronize a network of machines. NTP runs on User Datagram Protocol (UDP), which in turn runs on IP. NTP Version 3 is documented in RFC 1305. This module describes how to …

Sep 19, 2024 · Cisco routers and switches can use three different NTP modes: NTP client mode. NTP server mode. NTP symmetric active mode. The symmetric active mode is used between NTP devices to synchronize with each other, it’s used as a backup mechanism when they are unable to reach the (external) NTP server.

NTP sets the source IP address for all NTP packets based on the address of the interface through which the NTP packets are sent. You can configure NTP to use a specific source IP address.

NTP allows you to create a peer relationship between two networking devices. A peer can provide time on its own or connect to an NTP server. If both the local device and the remote peer point to different NTP servers, your NTP service is more reliable.

Jul 7, 2014 · This lesson explains how to configure NTP on your Cisco network devices including access-control and authentication.

Cisco routers and switches can use three different NTP modes: NTP client mode. NTP server mode. NTP symmetric active mode. The symmetric active mode is used between NTP devices to synchronize with each other, it’s used as a backup mechanism when they are unable to reach the (external) NTP server.

Apr 2, 2025 · This tutorial explains how to configure NTP Server and NTP Client in Cisco Router step by step with practical example. Learn basic concepts of NTP such as what NTP is, how NTP works, NTP stratum levels, meaning of synchronized and un-synchronized NTP clock in detail.

Jun 10, 2009 · W32Time uses Simple Network Time Protocol (SNTP a subnet of NTP) for time synchronization. SNTP and NTP use the same network-packet format. The main difference between SNTP and NTP is that SNTP doesn't provide …

Jun 22, 2009 · You can configure SNTP to request and accept packets from configured servers or to accept NTP broadcast packets from any source. When multiple sources are sending NTP packets, the server with the best stratum is selected.

Apr 20, 2020 · Configuring a Cisco IOS device (router/switch) is probably one of the easiest things that you can do. But there is a little homework you should to do make sure you implement a NTP configuration that will perform well. Before you start, you need to determine your NTP strategy.