By adding an id to your button declaration and by accessing the textbox value through JQuery, you're actually violating the main concept behind KnockoutJS and the two-way data binding concept. Instead, your button declaration should be something like:
<button type="button" class="btn btn-primary" data-bind="click: doSomething">Create connection</button>
And your textbox should be declared like:
<input type="text" data-bind="value: doSomethingParameter" />
In your ViewModel file, you must declare an observable "doSomethingParameter" and access its value through the function "doSomething":
self.doSomethingParameter = ko.observable();
self.doSomething= function () {
alert(self.doSomethingParameter());
};