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Satellite internet has come a long way since becoming a widely available connectivity option in the mid 2000s. Back then, while it was an upgrade from dial-up service, it was still in its infancy technology-wise. 虽然它在速度上的不足，但它在可用性上弥补了这一点.
As urban and suburban areas moved from dial-up to faster DSL service over phone lines — and later cable and fiber — people outside those population centers were already being left behind in what would become known as “the digital divide.” The infrastructure required to get a wired connection to every home simply isn’t scalable in areas with lower population density. It’s not uncommon even today for homeowners outside the cable/fiber zone to get quotes of $10,000或以上 把电缆或光纤带到他们的住所.
不像通过电缆提供的服务, DSL, 或纤维, satellite internet only requires a small antenna on a home or business. 信号从卫星直接到达天线盘, and the only cable needed is a short one to connect the outdoor terminal to the modem inside the building.
作为卫星互联网技术的领导者, Viasat has continually worked to improve service with higher-capacity satellites and vastly improved ground networks that provide coverage across 99% of the U.S.,包括 偏远及农村地区. Our upcoming ViaSat-3 global constellation is designed to bring even faster speeds and greatly increased capacity to handle data.
Some challenges still remain, and one of them people ask about is “latency.“在通信领域, latency refers to how long a signal takes to get from Point A to Point B and back again. Whether it’s fiber, cable, DSL or satellite, there’s always a certain amount of delay, or latency.
从卫星发出的无线电波以光速传播, 但由于信号必须传播的距离更远, 延迟比地面提供商高. 有线网络信号, 例如, 平均延迟可能为30毫秒(ms), 而地球静止轨道卫星发出的信号可能是600毫秒.
如果只有半秒，这对网络信号有什么影响?
In most cases, it doesn’t — or the effect is so minimal as to be barely noticeable. hg皇冠官网估计 对延迟敏感的互联网流量低于10%.
在其 最新的《hg皇冠老牌》, Sandvine reported that about 58% of internet traffic is streaming video, 哪个不会受到延迟的很大影响. The only delay would be at the outset when the stream is starting, but once it’s on, it’s on. Any buffering during video playback — satellite or terrestrial — is likely due to slow connection speeds or network congestion, 不延迟.
剩下的大部分互联网流量是流媒体音频, 社交媒体, 电子商务, 以及其他通常对延迟不敏感的应用程序.
以下是按类别划分的更多细节:
游戏和延迟
在线游戏是高延迟可能成为一个因素的领域. Because of the split-second decisions and movements required in something like a sports or “shooter” game, 来自卫星的更高延迟可能会产生很大的不同. 有些游戏在延迟超过100毫秒或200毫秒时无法使用, 而其他的, 回合制策略游戏完全不会受到影响.
根据Sandvine的报告, 只有4%的流量与游戏有关, 并非所有这些都对延迟敏感.
网页浏览
网站是由很多部分组成的, 当我们打开一个网站, 这些片段开始在互联网上流动，以“构建”网站. 如果你曾经打开过一个慢速连接的网站, 你已经体验过这个过程需要多长时间. 如果网速快，你可能根本注意不到.
Earlier satellite internet service was challenged to overcome the latency delay to allow webpages to load faster. Viasat pioneered the use of software to improve page-load speed over satellite. 这就产生了 hg皇冠官网浏览器, created specifically to improve service over any satellite connection. 浏览器使用安全的“提示”服务, which remembers details of how a site is put together and serves them as needed. The browser respects the security of HTTPS while still helping improve page-load time and overall speed.
The hg皇冠官网浏览器 can also block unwanted content such as privacy trackers, 广告, 而恶意软件帮助用户提供了更安全的, 更私密的浏览体验.
流媒体视频
有这么多的数据通过我们的网络是视频流, 这是一个我们会遇到很多问题的领域. 如上所述, most of the latency associated with video streaming comes primarily at the very beginning. 你可以把它比作两条花园软管——一长一短. 如果你同时打开两个水龙头, 矮的那个会更快地开始浇花, 但一旦长一点的赶上来, 它们是相等的.
延迟也会在一定程度上减慢倒带和快进速度.
Viasat has invested a lot of time and effort into improving what’s called “video shaping” — a way to deliver those digital packets of information as efficiently as possible to reduce those startup times and minimize data usage.
语音和视频聊天
One other area where latency has a small effect is with internet phone service, or VoIP. People talking over satellite with VoIP may notice a slight delay at first, 但随着耳朵的调整，它很快就变得不那么明显了.
Viasat为我们的住宅和商业计划提供VoIP服务, 我们成千上万的订阅者都很高兴看到它. It’s particularly important in remote areas where landline service isn’t available — and cell service doesn’t reach.
With video-chat, the slight delay is less noticeable because we can see one another. 与一些媒体报道相反, services like Zoom or FaceTime work just fine over satellite — with just that slight initial delay.
Other applications sometimes impacted by higher latency are virtual private networks, or VPNs. 有些根本不工作，而另一些可能工作得很好. 这取决于它们如何配置.
展望未来
While latency does present some challenges for satellites in geostationary orbit, Viasat已经取得了很大的进步，使它不再是一个问题. We’re also exploring how hybrid networks (satellite paired with LTE or DSL, 例如, or even with low-Earth orbit satellites) can handle latency-sensitive traffic by making routing decisions based on latency. That has the potential to combine the coverage and capacity power of our large geostationary satellites in high orbit with the lower latency inherent in ground-based services and satellites closer to Earth. Advanced networking configurations using artificial intelligence can make instant decisions about each packet of data, 为工作选择最好的道路.
That “best of both worlds” approach has the potential to greatly reduce latency impacts associated with satellite internet.