Jan 18, 2017 · Poorly-configured NTP servers can be used for Reflective DDOS attacks, and some devices provide NTP service inadvertently, which exacerbates the port’s malicious use. Port 135/TCP : NetBIOS is a network file sharing protocol and is also known as Common Internet File System or LanManager.

Jul 26, 2013 Enterprise Network Time Servers | Microsemi Multiple NTP ports: Having a time server that supports offers multiple NTP ports accommodates modern networks as well as ones destined to be upgraded at some future point in time. If your network is going to grow, or security is important, you want your time server to keep pace with it. NIST Internet Time Service Users are *strongly* encouraged to upgrade to the network time protocol (NTP), which is both more accurate and more robust. 2. Users of the NIST "DAYTIME" protocol on tcp port 13 are also strongly encouraged to upgrade to the network time protocol, which provides greater accuracy and requires less network bandwidth. pool.ntp.org: How do I setup NTP to use the pool?

Service overview and network port requirements for Windows

In most cases it's best to use pool.ntp.org to find an NTP server (or 0.pool.ntp.org, 1.pool.ntp.org, etc if you need multiple server names). The system will try finding the closest available servers for you. If you distribute software or equipment that uses NTP, please see our information for vendors. NTP (Network Time Protocol) - study-ccna.com Network Time Protocol (NTP) is an application layer protocol used for clock synchronization between hosts on a TCP/IP network. The goal of NTP is to ensure that all computers on a network agree on the time, since even a small difference can create problems.

Jul 10, 2011

There are two levels, or tiers, of Network Time Protocol (NTP) time servers that are available on the Internet. The NTP is defined in Request for Comments (RFC) 1305. The first-level time servers are primarily intended to act as source time servers for second-level time servers. 9.9. ntp.conf and dhcp. If your /etc/ntp.conf is being automatically overwritten, this may be due to DHCP. Either run your dhcpd (dhcp server) with the dhcpd.conf option "option ntp-servers ;", or run your dhcpcd (dhcp client) with the -N arg to prevent ntp.conf from being rewritten at all. NTP runs on UDP port 123. The Windows 2000 version of this service uses Simple Network Time Protocol (SNTP). SNTP also runs on UDP port 123. When the Windows Time service uses a Windows domain configuration, the service requires domain controller location and authentication services. Therefore, the ports for Kerberos and DNS are required. You can also use the continental zones (For example europe, north-america, oceania or asia.pool.ntp.org), and a country zone (like ch.pool.ntp.org in Switzerland) - for all these zones, you can again use the 0, 1 or 2 prefixes, like 0.ch.pool.ntp.org. Note, however, that the country zone might not exist for your country, or might contain only server 0.north-america.pool.ntp.org server 1.north-america.pool.ntp.org server 2.north-america.pool.ntp.org server 3.north-america.pool.ntp.org. In most cases it's best to use pool.ntp.org to find an NTP server (or 0.pool.ntp.org, 1.pool.ntp.org, etc if you need multiple server names). The system will try finding the closest available servers