Network Time Protocol (NTP)
Precise and pervasive network synchronization is vital to today’s enterprise and telecom networks for reasons such as security, quality of service, legal compliance, fault diagnosis and forensic analysis. Synchronization is ever more critical as networks now transport more data at higher rates to an increasingly diverse set of rapidly growing applications. Different applications, different networks, different requirement sets, different sync technologies — Symmetricom helps you sort it all out.
As you read this, your network of workstations and servers, each with their own clock, are time stamping files, email, transactions, etc., all the while your server logs are recording every manner of transaction in the event you need that information. At some point during the day it is quite likely that automatic processes such as archiving, directory synchronization, cron jobs, etc. will execute and alter files based on time stamps. Fundamental to all of this is the belief that the time is correct. This paper describes why “close enough” is no substitute for accurate network time and why network time synchronization is critically important.
Carrier services, networks and support systems have changed rapidly using the Internet protocol as an underlying technology. Synchronization of a large number of widely distributed elements has become a mission critical foundation for the packet networks. Network Time Protocol has served this purpose well, but network engineers can no longer rely on enterprise class equipment and deployment models typical of traditional datacenter implementations. Applications ranging from the IMS architecture to femtocell services require an NTP solution that provides higher accuracy, availability, security and capacity. This paper describes the characteristics of a carrier grade NTP solution and highlights its importance in critical applications.
Previous whitepapers in this series have discussed the essential network timekeeping attributes of accuracy, reliability and security. While these attributes can be considered paramount, as humans we expect technology to be easy to deploy, otherwise it belongs in the lab and not part of mission critical essential network operations. This paper explores various operational areas of network time servers and the EASY aspects that you should expect when you deploy them.
Asynchronous Transfer Mode (ATM), conceived as a multi-service technology, is now the standard of choice for broadband networks. It is the world’s most widely deployed backbone technology. ATM allows a wide range of traffic types (voice, video, data, etc.) to be multiplexed in a single network. A key benefit of ATM technology is its ability to provide quality of service (QoS) guarantees to applications.
More and more enterprises are using IP telephony solutions based on Cisco networking solutions. But many customers are overlooking an important part of the system architecture—the need to synchronize the infrastructure design with an external network time server. Proper clock synchronization is critical to ensuring good performance, improving troubleshooting, and producing accurate call detail records (CDRs) for billing.
As we accelerate into the New World of VoIP we assume we can leave some of the trappings of wireline telecom behind, such as the need for synchronization. After all, an IP network is about as asynchronous as it gets. While this may be true in some respects, precise time and synchronization continue to permeate many areas of IP telephony operations. Customer expectations of voice quality and service reliability remain unchanged, and as a result, the need for precise time remains unchanged though it manifests itself in different ways. The bottom line is that trying to design a VoIP network without considering network synchronization is probably the shortest path to realizing that you need it.
Proper synchronization in a telecommunications network is critical to its operation. Inadequate synchronization compromises quality of service, leading to such impairments as data retransmission, digital video freeze and distortion, and severe degradation of encrypted services. In particular, SONET and SDH require that careful attention be paid to synchronization; otherwise frequent pointer movements lead to high levels of jitter and wander and compromised service quality.
Organizations today need network time synchronization that ensures the integrity of network operations and applications yet needs little in the way of management overhead. It’s hard to imagine a company that would knowingly tolerate only some of its processes running on time or only some of its timestamps being accurate — especially if they realize how easy and inexpensive good network timekeeping can be to accomplish. To make time both pervasive and accurate, five essential elements must be present.
Network Time Synchronization is becoming more important than ever in today’s networks as companies have come to rely on their networks for all their communication needs. Since the 1990’s we have seen an explosion of TCP/IP network usage and de-centralized network resources. The goal of having one network running many services, instead of a different disparate network per service, is a valid and more cost-effective approach to Enterprise communication needs.
This paper looks at why it’s important for any network to keep its devices in sync and examine the security implications – and financial ramifications - of improper network time. It also explains an approach to keeping proper time that doesn’t require you to leave holes in your network defenses.
The need for Telcos to deliver the triple play of voice, video and data in order to compete with services offered by cable companies has reignited the focus on broadband optical access systems based on Passive Optical Networking (PON). PON components are key to unlocking the bandwidth of fiber. This paper specifically addresses GPON (Gigabit PON) applications and the associated synchronization requirements for the smooth transmission of real-time services over broadband networks.
