Most people have heard of latency, which is a measure of the average delay of data packets on a network. There is another important measure of network quality that is rarely talked about. Jitter is the variance in the delays of signals being delivered through a broadband network connection. Jitter occurs when the latency increases or decreases over time. We have a tendency in the industry to oversimplify technical issues; we take a speed test and assume the answer that pops out is our speed. Those same speed tests also measure latency, and even network engineers sometimes get mentally lazy and are satisfied to see an expected latency number on a network test. But in reality, the broadband signal coming into your home is incredibly erratic. From millisecond to millisecond, the amount of data hitting your home network varies widely. Measuring jitter means measuring the degree of network chaos. Fully understanding the causes of jitter in any specific network is a challenge because the causes can be subtle. It’s often hard to pinpoint a jitter problem because it can be here one millisecond and gone the next, but it’s something we should be discussing more. A lot of the complaints people have about their broadband connection are caused by too-high jitter.

[Doug Dawson is President of CCG Consulting.]

A new generation of high-speed radio frequencies is allowing phone companies to grab a larger share of home internet subscriptions from cable TV operators. Of the 3.7 million new broadband customers signed up by the five biggest cable and telephone companies last year, 22 percent went to wireless connections, according to data compiled by Bloomberg. T-Mobile and Verizon grabbed 819,000 subscribers, a significant bite out of the broadband market. Their weapon, new fixed wireless connections to the home using 5G frequencies. AT&T doesn’t break out its wireless internet customer numbers and its business is still small. Comcast and Charter Communications, on the other hand, saw the number of new broadband subscribers they signed up fall by 40 percent. While the slowdown was expected, given the surge of people who geared up their home networks to ride out the COVID-19 pandemic in 2020, the tallies from the cable giants were lower than Wall Street expected.

US safety regulators have received more than 100 pilot reports of possible interference from 5G wireless signals -- including three near Chicago O’Hare International Airport -- since the new mobile phone service began less than two weeks ago. The reports of anomalies on aircraft devices known as radar altimeters are being reviewed by the Federal Aviation Administration (FAA). Interference from the new 5G service has been ruled out in many of the cases, and it remains unclear whether the others indicate a safety hazard or just pilots being overly cautious. “We are using our established safety-reporting systems to look into a handful of reports of possible 5G interference,” the FAA said in a statement. “So far none of these reports have been validated.” But the reports, combined with the vital role altimeters play in safety, help explain why the FAA has taken such a stringent approach to minimizing risks from the new wireless signals. New 5G mobile phone service introduced by AT&T and Verizon operate on so-called C-band frequencies that are close to those used by radar altimeters. The impact on aviation in the US has so far been minimal as the FAA and wireless companies have agreed to at least temporarily restrict placement of cell towers near airports. But with wireless companies eager to activate hundreds more cell towers near airports and to expand into new frequency bands, the issue remains far from settled.

T-Mobile added 2.9 million phone subscribers in 2021 and forecast its midband 5G network would reach 300 million people by 2023. In three months ending December 31, T-Mobile added 844,000 postpaid customers, a subscriber category prized by carriers for long-term revenue and overall success. It also added 224,000 net customers of its high-speed internet service. The country's third-largest carrier also repeated some achievements it had previously announced; its Ultra Capacity 5G network, made up largely of the 2.5GHz midband spectrum acquired from the Sprint merger, reached 210 million people by the end of 2021, exceeding its goal by 10 million. In a swipe at other carriers, T-Mobile claimed that it will take its competitors years to reach that number. That seems to be supported by the rivals' own estimates, with AT&T expecting to reach 200 million people by the end of 2023. In that time, T-Mobile said it will grow its Ultra Capacity 5G network to reach 260 million people by the end of this year and 300 million people by the end of 2023. This expansion includes more midband service as T-Mobile integrates the small amount of C-band spectrum the carrier bought in 2021 and the portion of 3.45 GHz spectrum acquired in an FCC auction last year. It's unclear how the carrier's Ultra Capacity 5G network will expand with both spectrum tranches, though customers should expect C-band service and 3.45GHz midband integrated in 2023.