链路层QoS技术主要针对ATM(Asynchronous Transfer Mode，异步传输模式)、帧中继、令牌环等链路层协议支持QoS。作为一种面向连接的技术，ATM提供对QoS最强有力的支持，而且可以基于每个连接提供特定的QoS保证。帧中继网络确保连接的CIR(Committed Information Rate，承诺信息速率)最小，即在网络拥塞时，传输速度不能小于这个值。令牌环和更新的IEEE802.1p标准具有区分服务的机制。
链路层QoS技术主要针对ATM(Asynchronous Transfer Mode，异步传输模式)、帧中继、令牌环等链路层协议支持QoS。作为一种面向连接的技术，ATM提供对QoS最强有力的支持，而且可以基于每个连接提供特定的QoS保证。帧中继网络确保连接的CIR(Committed Information Rate，承诺信息速率)最小，即在网络拥塞时，传输速度不能小于这个值。令牌环和更新的IEEE802.1p标准具有区分服务的机制。
The lead from Wall Street offers little clarity as the major averages opened lower on Friday and then bounced back and forth across the unchanged line, finally finishing mixed and little changed.The Dow added 33.18 points or 0.10 percent to finish at 34,798.00, while the NASDAQ eased 4.54 points or 0.03 percent to close at 15,047.70 and the S&P 500 rose 6.50 points or 0.15 percent to end at 4,455.48. For the week, the Dow rose 0.6 percent, the NASDAQ added 0.1 percent and the S&P gained 0.5 percent.The lackluster performance on Wall Street came on uncertainty about the outlook for the markets following recent volatility.
Telegram Auto-Delete Messages in Any Chat
Some messages aren’t supposed to last forever. There are some Telegram groups and conversations where it’s best if messages are automatically deleted in a day or a week. Here’s how to auto-delete messages in any Telegram chat. You can enable the auto-delete feature on a per-chat basis. It works for both one-on-one conversations and group chats. Previously, you needed to use the Secret Chat feature to automatically delete messages after a set time. At the time of writing, you can choose to automatically delete messages after a day or a week. Telegram starts the timer once they are sent, not after they are read. This won’t affect the messages that were sent before enabling the feature.
