public String getDomainName() {
        StringBuilder recordPtr = new StringBuilder(75);
        int segmentWidth = isIpv6() ? 4 : 8;

        int start = suffixLength() - (segmentWidth - (prefixLength % segmentWidth)) % segmentWidth;
        for (int i = start; i < addressLength; i += segmentWidth) {
            int segment = addressInteger.shiftRight(i)
                                        .and(BigInteger.ONE.shiftLeft(segmentWidth).subtract(BigInteger.ONE))
                                        .intValueExact();

            recordPtr.append(isIpv6() ? Integer.toHexString(segment) : segment).append(".");
        }

        return recordPtr.append(isIpv6() ? "ip6" : "in-addr").append(".arpa.").toString();
    }
@return the .arpa address for this CIDR block, does not include bit outside the prefix
vespajlib/src/main/java/ai/vespa/net/CidrBlock.java