While a protocol as a whole, may be comprised of more than one header type that it uses for communication purposes to exchange information such as state and transmit application specific data. This is the reason why sometimes a protocol is described as a protocol suite.
Since January 1, 2006, U.S. employers have been allowed to amend their 401(k) plan document to allow employees to elect Roth IRA type tax treatment for a portion or all of their retirement plan contributions. The same change in law allowed Roth IRA type contributions to 403(b) retirement plans. Employees can roll their Roth 401(k) contributions over to a Roth IRA account upon termination of employment. 2  It is the employer's decision whether to provide access to the Roth 401(k) in addition to the traditional 401(k).
In 2015, you can make a contribution of up to $24,000 to your 401(k), 403(b) or governmental 457(b) plan ($18,000 regular and $6,000 catch-up contributions) and $6,500 to a Roth IRA ($5,500 regular and $1,000 catch-up IRA contributions) for a total of $30,500 for 2015.01(k) , 403(b) and 457(b) governmental plans that have designated Roth accounts may offer in-plan Roth rollovers. Plan sponsors have until the end of 2014 to amend a plan to permit a new category of in-plan Roth rollovers in 2013 and 2014.