I was responsible for developing new software for an existing switch.

当时我负责为一个老交换机开发新的软件。

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In Type 3 situations, there are few alternatives, but the ability to switch without difficulty creates a threat that companies can use to negotiate concessions from existing suppliers.

在第三种情况下，几乎没有其他选择，但毫无困难地转换的能力造成了一种威胁，企业可以利用这种威胁与现有供应商谈判让步。

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Whether you plan to tight-couple some Web services or redesign some existing Web services to be able to make the coupling switch, you should set a performance measurement goal.

无论您是否计划对某些Web Services进行紧密耦合或重新设计某些现有Web Services，以便能够进行耦合切换，则应该设定一个性能测定目标。

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Telewest's self-install package does away with the need for a visit by one of the company's engineers and lets existing customers swiftly switch on a broadband service.

BBC: Cable clips,

Existing customers are ready to switch, and potential buyers are ready to consider other options.

FORBES: Weak Rivals Ensure Apple's Dominance For Another iPhone Generation

Apple's challenge is that getting people to buy an iPod, a new type of device, is easier than getting them to switch loyalties in an existing product category.

ECONOMIST: The iPod has turned Apple into a superbrand