چرا wildcard به جای subnet mask ؟

سلام
من که نفهمیدم چرا IOS اینطوری IP رو j توی کانفیگش نگه میداره ؟ اگر تا حالا بهش فکر کردین به من هم بگید
ممنون
Net id + wildcard نگه میداره چرا با subnet mask نگه نمی داره ؟[LEFT]Two features of the mechanics of the network command require a little extra attention. First, IOS may convert the address portion of the network address wc-mask command before putting the command into the running-config. Just as IOS does for the address/WC mask combinations for the access-list command, IOS inverts the WC mask and then performs a Boolean AND of the address and mask. For example, if you type the network 10.1.1.1 0.0.255.255 command, IOS inverts the WC mask (to 255.255.0.0), ANDs this value with 10.1.1.1, resulting in 10.1.0.0. As a result, IOS stores the command network 10.1.0.0 0.0.255.255.
CCNP ROUTE page 25
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